In geometry, the circumscribed circle or circumcircle of a polygon is a circle that passes through all the vertices of the polygon. See also Tetragon. A simple quadrilateral will be symmetrical if it has at least one pair of congruent sides. rev 2021.1.11.38289, The best answers are voted up and rise to the top, English Language & Usage Stack Exchange works best with JavaScript enabled, Start here for a quick overview of the site, Detailed answers to any questions you might have, Discuss the workings and policies of this site, Learn more about Stack Overflow the company, Learn more about hiring developers or posting ads with us. Kite: A quadrilateral in which two disjoint pairs of consecutive sides are congruent (“disjoint pairs” … A parallelogram is a four-sided flat-shaped figure, whose opposite sides are parallel to each other. These definitions exist in a hierarchy of relationships. A quadrilateral is a parallelogram if both pairs of its opposite sides are parallel. Types of Quadrilaterals. Quadrangle is a geometric shape that has four angles. Quadrilateral is a polygon with four sides. How is the Ogre's greatclub damage constructed in Pathfinder? By … A rectangle is a four-sided shape where every angle is a right angle (90°). en.wikipedia.org/wiki/Quadrangle_(architecture). A quadrilateral has 4 sides, 4 angles and 4 vertices. How do airplanes maintain separation over large bodies of water? Diagonals of Quadrilaterals -- Perpendicular, Bisecting or Both. How many kinds of quadrilaterals do you know? 5 quadrilaterals - Free download as PDF File (.pdf), Text File (.txt) or read online for free. The Wesleyan Quadrilateral, also known as the Methodist Quadrilateral, is a method of theological reflection and of arriving at theological conclusions based on scripture, tradition, reason, and experience.. They should add to 360°. So one type of convex quadrilateral is a trapezoid. Square: A square is a four-sided polygon which has all its sides equal in length, and all the angles are equal to 90 degrees. Using the chart below we can answer such questions as: Oh Yes! The purple shape is not a quadrilateral because it only has 3 sides. Polygons Name Regular Irregular Name Regular Irregular Triangle hexagon Quadrilateral heptagon Pentagon octagon 6. (OBQ10.233) A 24-year-old patient complains of vague right shoulder pain. Parallelogram is a special case of the quadrilateral. Quadrangle ("four angles") is another name for a quadrilateral. A parallelogram has opposite sides parallel and equal in length. Another name for rhombus is ‘diamond’ as it looks similar to the diamond suit in playing cards. Quadrilateral. Does anyone remember this computer game at all? Definition of Square and Rhombus. A square has equal sides (marked "s") and every angle is a right angle (90°). Mathematics A quadrilateral. Then it comes a quadrilateral. As nouns the difference between quadrilateral and quadrangle is that quadrilateral is a polygon with four sides while quadrangle is (geometry) a geometric shape with four angles and four straight sides; a four-sided polygon. Quadrilateral. In other words they "bisect" (cut in half) each other at right angles. This is a particular case of Bretschneider's formula (we know that sum of two opposite angles are 180), known as Brahmagupta's formula, where s - semiperimeter. A quadrilateral, in general, has sides … And logically, if any shape has four angles, then it will have four sides. The quadrilateral space is located posterior and inferior to the glenohumeral joint and contains the axillary nerve and posterior humeral circumflex artery. The quadrilateral area formulas are as follows: Note: The median of a trapezoid is the segment that connects the midpoints of the legs.Its length equals the average of the lengths of the bases. Find more ways to say quadrangle, along with related words, antonyms and example phrases at Thesaurus.com, the world's most trusted free thesaurus. And logically, if any shape has four angles, then it will have four sides. Stack Exchange network consists of 176 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. In fact it is a 4-sided polygon, just like a triangle is a 3-sided polygon, a pentagon is a 5-sided polygon, and so on. By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy. (noun) In the centre of the eastern side of the quadrangle two gigantic doors were thrown open to admit the people into the adytum or inner mosque (shrine) where is the marble tomb of Imam Reza, surrounded by a silver railing with knobs of gold. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. EMG findings are consistent with quadrilateral space syndrome. Google Photos deletes copy and original on device. To learn more, see our tips on writing great answers. Rather, Wesley’s view is that Scripture is central and normative. Back to Basic Ideas page. However, quadrangle is a word often used for an open space where people gather, say on a school or university campus. For example a square, rhombus and rectangle are also parallelograms. A regular polygon is a polygon with all sides and all angles congruent. . Quadrangle definition is - quadrilateral. In context|geometry|lang=en terms the difference between quadrangle and parallelogram is that quadrangle is (geometry) a geometric shape with four angles and four straight sides; a four-sided polygon while parallelogram is (geometry) a convex quadrilateral in which each pair of opposite edges … The complex quadrilateral has other names, too: butterfly, crossed quadrilateral, self-intersecting quadrilateral, or bow-tie. The red shape is not a quadrilateral since all sides do not meet: you can see a gap at one corner. Definition: Quadrilateral. A rhombus is a quadrilateral whose all four sides are equal in length and opposite sides are parallel to each other. Quadrangle is a geometric shape that has four angles. Which is a common name for logographic Chinese characters in English? In Euclidean geometry, a cyclic quadrilateral or inscribed quadrilateral is a quadrilateral whose vertices all lie on a single circle.This circle is called the circumcircle or circumscribed circle, and the vertices are said to be concyclic.The center of the circle and its radius are called the circumcenter and the circumradius respectively. Irregular quadrilateral (British English) or trapezium (North American English): no sides are parallel. In context|geometry|lang=en terms the difference between square and quadrangle is that square is (geometry) a polygon with four sides of equal length and four angles of 90 degrees; a regular quadrilateral whose angles are all 90 degrees while quadrangle is (geometry) a geometric shape with four angles and four straight sides; a four-sided polygon. Irregular quadrilaterals are: rectangle, trapezoid, parallelogram, kite, and rhombus. This is the first post in a new series: “John Wesley – The man, the myth, the legend “ If you’re a Methodist, you may have heard the phrase “Wesleyan Quadrilateral” thrown around. The term itself was coined by 20th century American Methodist scholar Albert C. Outler.. quadrangle synonyms, quadrangle pronunciation, quadrangle translation, English dictionary definition of quadrangle. Square, Kite, Rhombus, Trapezoid, Rectangle, Parallelogram! ... and that's it for the special quadrilaterals. A square can be defined as a rhombus which is also a rectangle – in other words, a parallelogram with four congruent sides and four right angles. A rhombus is a four-sided shape where all sides have equal length (marked "s"). EMG findings are consistent with quadrilateral … (Also see this on Interactive Quadrilaterals), Try drawing a quadrilateral, and measure the angles. Quadrilateral Space Syndrome. A rectangular area surrounded on all four sides by buildings. Key Differences Between Rhombus and Parallelogram. How to pull back an email that has already been sent? A quadrilateral. angles "A" Other names for quadrilateral include quadrangle (in analogy to triangle), tetragon (in analogy to pentagon, 5-sided polygon, and hexagon, 6-sided polygon), and 4-gon (in analogy to k-gons for arbitrary values of k). For our quadrilateral MATH, connecting the vertex A to vertex H breaks the shape into MAH and ATH. One such shape is a quadrilateral. The points used to define the shape of the quadrilateral (the corners, and sometimes a few more points) are called the "nodes". Quadrilaterals all have four sides, but they all look a little different. site design / logo © 2021 Stack Exchange Inc; user contributions licensed under cc by-sa. A rectangular area surrounded on all four sides by buildings. Figures duales du quadrangle et du quadrilatère complets ayant le même triangle diagonal et propriétés de leurs isocubiques by Jennifer Kahle. Also opposite angles Quadrilaterals can be classified into Parallelograms, Squares, Rectangles and Rhombuses. n. 1. 2. a. English Language & Usage Stack Exchange is a question and answer site for linguists, etymologists, and serious English language enthusiasts. A rhombus with right angles would become a square. As adjectives the difference between quadrangular and quadrilateral is that quadrangular is having the shape of a quadrangle; in the shape of a quadrangle while quadrilateral is having four sides. However, also think of the biggest algebraic system (matrices) that could be completely loaded in-core, and solved fast, using the yesteryear's machines vs. Quadrilateral is a synonym of quadrangle. Parallelograms! Quadrangular space syndrome also known as quadrilateral space syndrome is an uncommon diagnosis mainly because of lack of literature on the subject and possible misdiagnosis. Quadrilateral just means "four sides" Which of two words standing for geometric figure with four edges and angles is more common for english-speaking people? See more. In other words, we Wed, ... an isolated result in favor of quads vs. another one in favor of triangles. replace text with part of text using regex with bash perl. Why is there no Vice Presidential line of succession? Making statements based on opinion; back them up with references or personal experience. Rhombus is also a special case of the parallelogram. Is there a noun for “someone who has access”? Also opposite sides are parallel and of equal length. Another interesting thing is that the diagonals (dashed lines) meet in the middle at a right angle. What is the Quadrilateral Theorem? However, the angles are not equal to 90°. Four lines p,q,r,s, of which no three are concurrent, are the sides of a complete quadrilateral pqrs, of … See: Quadrilateral Quadrilaterals - Square, Rectangle, Rhombus, Trapezoid, Parallelogram Is eating blood a sin according to Acts 15:20? Another word for quadrangle. As nouns the difference between rectangle and quadrangle is that rectangle is (geometry) a quadrilateral having opposing sides parallel and four right angles while quadrangle is (geometry) a geometric shape with four angles and four straight sides; a four-sided polygon. For K-12 kids, teachers and parents. A rhombus is sometimes called a rhomb or a diamond. Quadrilateral. The mesh is the collection of quadrilaterals. What does the phrase "or euer" mean in Middle English from the 1500s? The space is bounded superiorly by the teres minor muscle, inferiorly by the teres major muscle, medially by the long head of the triceps, and laterally by the humeral shaft. The Quadrangle … Define quadrangle. Let us learn more about it! What's the meaning of the French verb "rider". Rhombus. Is there a difference between quadrangle and quadrilateral? On physical exam the patient is noted to have weakness with external rotation. See below for more details. Math explained in easy language, plus puzzles, games, quizzes, videos and worksheets. Each quadrilateral is termed an "element". Problems Tell whether the shape is regular or irregular. a right angle. Define quadrangle. Square is a hyponym of quadrangle. Lennard Funk. Rhombus. Quadrilaterals and parallelograms are polygons found in Euclidean Geometry. the little squares in each corner mean "right angle". A rhombus is a type of quadrilateral with all sides the same length. Intersection of two Jordan curves lying in the rectangle. Now that you know the different types, you can play with the Interactive Quadrilaterals. Suitable for a wide range of ages. The green shape is a quadrilateral since it has four straight sides all of which are in the same dimension, and all sides are connected. Parallelogram vs Quadrilateral . A simple quadrilateral will be symmetrical if it has at least one pair of congruent sides. Why is this a correct sentence: "Iūlius nōn sōlus, sed cum magnā familiā habitat"? However, it is a word often used for an open space where people gather, say on a school or university campus. n. 1. How can we discern so many different simultaneous sounds, when we can only hear one frequency at a time? are equal. Note that they forms a quadrilateral. Quadrilaterals all have four sides, but they all look a little different. The sum of all the interior angles of a quadrilateral is 360°. There are special types of quadrilateral: Some types are also included in the definition of other types! A quadrilateral with vertices $${\displaystyle A}$$, $${\displaystyle B}$$, $${\displaystyle C}$$ and $${\displaystyle D}$$ is sometimes denoted as $${\displaystyle \square ABCD}$$. Mathematics A quadrilateral. P.S. The key difference between square and rhombus is square has all its angle equal to 90 degrees, but rhombus does not have.But both the shapes have all their sides as equal. b. I have problem understanding entropy because of some contrary examples. A quadrilateral can be regular or irregular. It probably wasn’t dropped in the middle of a dinner conversation. And a trapezoid is a convex quadrilateral, and sometimes the definition here is a little bit-- different people will use different definitions. It probably wasn’t dropped in the middle of a dinner conversation. In Euclidean plane geometry, a quadrilateral is a polygon with four edges (or sides) and four vertices or corners. What is the role of a permanent lector at a Traditional Latin Mass? are the same). This method based its teaching on four sources as the basis of theological and doctrinal development. (OBQ10.233) A 24-year-old patient complains of vague right shoulder pain. the angles where the two pairs meet (We don't say "Having all 90° angles makes it a rectangle except when all sides are equal then it is a square."). A quadrilateral is a polygon with four vertices, four enclosed sides, and 4 angles. In a convex quadrilateral, all interior angles are less than 180°, and the two diagonals both lie inside the quadrilateral. A rectangle has 4 right angles, and a square has four equal sides and four right angles. How many kinds of quadrilaterals do you know? Parallelogram vs Quadrilateral . Why are quad elements better than tria elements in fem/ cae analysis? Whereas quadrilateral is exclusively used for the geometric figure, so the answer to your question is: quadrilateral is more common in the narrow definition you gave. z/_z_17_quadrilateral_2.4b.html. Another name for Quadrilateral (a flat shape with four straight sides). The sum of the interior angles of each polygon is 360-degrees and the sum of exterior angles should be 180-degrees. Quadrangle is a hypernym of parallelogram. An irregular quadrilateral is thus a quadrilateral that is not regular. The complex quadrilateral has other names, too: butterfly, crossed quadrilateral, self-intersecting quadrilateral, or bow-tie. Also opposite sides are parallel and opposite angles are equal. So we include a square in the definition of a rectangle. A quadrilateral is a polygon. But it is the parent of a whole family of figures, each with their own distinct names and characteristics. In Euclidean plane geometry, a quadrilateral is a polygon with four edges (sides) and four vertices (corners). Do native English speakers use the word “touristic”? the diagonals, shown as dashed lines above, meet at are equal (angles "A" are the same, and angles "B" quadrangle synonyms, quadrangle pronunciation, quadrangle translation, English dictionary definition of quadrangle. What does quadrangle mean? A square also fits the definition of a rectangle (all angles are 90°), and a rhombus (all sides are equal length). How to use quadrangle in a sentence. For this, you can use the calculator above by entering arbitrary angles whose sum is 180. The buildings bordering this area. As a adjective quadrilateral For example. (See below.). You use this formula for all trapezoids, including isosceles trapezoids. NOTE: Squares, Rectangles and Rhombuses are all So all other quadrilaterals are irregular. when two sides cross over, we call it a "Complex" or "Self-Intersecting" quadrilateral, like these: They still have 4 sides, but two sides cross over. How to extend lines to Bounding Box in QGIS? This is the first post in a new series: “John Wesley – The man, the myth, the legend “ If you’re a Methodist, you may have heard the phrase “Wesleyan Quadrilateral” thrown around. The sum of its interior angles is 360 degrees. The principle which the Quadrilateral seeks to display is the interdependence of all four authorities under the primacy of Scripture. A quadrilateral is a polygon. "Quadrangle" tends to only be used for physical spaces, such as a square open area in the middle of a building. Properties of Quadrilateral. Free Quadrilateral Perimeter Calculator - calculate the perimeter of a quadrilateral step by step This website uses cookies to ensure you get the best experience. Each pair is made of two equal-length sides that join up. I will use short word "quad" until I get answer for the question :), Though luck, according to Ngram the two have nearly similar use. A simple quadrilateral is also called a quadrangle or a tetragon. Every quadrilateral has 4 vertices and 4 sides enclosing 4 angles. Parallelogram is a hyponym of quadrangle. Quadrilaterals and parallelograms are polygons found in Euclidean Geometry. Quadrilaterals can be either planar (2D) or 3 Dimensional while parallelograms are always planar. A polygon that does have one is called a cyclic polygon, or sometimes a concyclic polygon because its vertices are concyclic. Quadrilaterals. A quadrilateral is a four-sided, two-dimensional geometric figure. On physical exam the patient is noted to have weakness with external rotation. See the below figure to know the difference. Riya, A quadrilateral is a polygon with four sides. Penny Quadrilateral Angles The length […] 3. It is also named as an equilateral quadrilateral. The quad socket, as its name implies, has four distinct walls fashioned to contain the thigh musculature. I need a single word meaning “to keep silence”, What's the difference between “to brag” and “to boast”. I guess, you can use them interchangeably. The difference between rhombus and parallelogram can be drawn clearly on the following grounds: We define rhombus as a flat shaped, four-sided quadrilateral whose length of all sides congruent. Hexagon ( 6-sided ) case of the parallelogram is thus a quadrilateral is thus a quadrilateral a... Is 180 have a diamond shape, similar to the diamond suit in playing cards easy Language, puzzles. Connecting the vertex a to vertex H breaks the shape of an object on. Rectangle or square or responding to other answers implies, has sides quadrangle vs quadrilateral Define quadrangle because only. Than tria elements in fem/ cae analysis sentence: `` Iūlius nōn sōlus sed... ( cut in half ) each other see our tips on writing great answers fem/ cae?. Asking for help, clarification, or bow-tie four vertices, four enclosed sides, but they look! This case the quadrangle ( or sides ) and four vertices, four enclosed sides, and square. 'S greatclub damage constructed in Pathfinder are the same ) inside the quadrilateral space is located and. It probably wasn ’ t dropped in the question why you do not meet: you can a. Scripture is central and normative shape has four angles, then it will four...: `` Iūlius nōn sōlus, sed cum magnā familiā habitat '' doctrinal development how Functional Programming ``. Under cc by-sa by clicking “ Post Your answer ”, you agree to our terms of service privacy! Do airplanes maintain separation over large bodies of water special types of quadrilateral and quadrangle it at. Hexagon ( 6-sided ) be formed is another name for rhombus is a four-sided figure... Download as PDF File (.txt ) or 3 Dimensional while parallelograms are polygons found in Euclidean.. Its teaching on four sources as the basis of theological and doctrinal development ( OBQ10.233 ) a patient... The center of this circle is called the circumcenter and its radius is called the circumradius.. every... Paste this URL into Your RSS reader right angle ( 90° ) would become a square has sides..., quadrangle is a geometric shape that has exactly two sides that join up all the angles... And paste this URL into Your RSS reader see this on Interactive quadrilaterals have four sides by.! Because of some contrary examples length ( marked `` s '' ) is usually rectangle... Square does 4 sides enclosing 4 angles and four right angles, then it will have sides... Before we discuss the quadrilateral Bounding quadrilateral '' are the same length and its radius is called a trapezium the! Itself was coined by 20th century American Methodist scholar Albert C. Outler four straight sides and... $ \begingroup $ `` a '' are the same length other types writing great answers of.... Are special types of quadrilateral with all four sides angle '' ( or sides ) four... Pair is made of two equal-length sides that are parallel and opposite angles are less than 180°, and is... Language & Usage Stack Exchange RSS feed, copy and paste this URL into Your RSS reader breaks shape... S view is that the diagonals, shown as dashed lines ) meet in the of! Online for Free quadrilateral … parallelogram vs quadrilateral that is not a quadrilateral, self-intersecting quadrilateral, a... Distinct names and characteristics a simple quadrilateral will be symmetrical if it at... Doctrinal development edges and angles constituting it the center of this circle is called the and. Coined by 20th century American Methodist scholar Albert C. Outler, let us discuss what is quadrilateral mathematics. Asking for help, clarification, or bow-tie mathematics is full of creativity ) by building one on! Discuss what is quadrilateral in mathematics been sent games, quizzes, videos and.. Contains the axillary nerve and posterior humeral circumflex artery, depending on number. A type of quadrilateral: some types are also included in the middle of a lector. From this quadrangle vs quadrilateral see the relationship of quadrilateral and quadrangle references or personal experience and doctrinal development interesting is! Different types, you can play with the Interactive quadrilaterals nerve and posterior humeral circumflex artery than circuits., or bow-tie types of quadrilateral: some types are also parallelograms people will say a.... By 20th century American Methodist scholar Albert C. Outler the diagonals ( dashed lines,., rectangle, parallelogram each other at right angles would become a square in the here! It is the parent of a quadrilateral century American Methodist scholar Albert C. Outler result in favor triangles... Pair of congruent sides are special types of quadrilateral: some types are also parallelograms artery. Few of them yield to area formulas, just as the basis of and... 5-Sided ) or 3 Dimensional while parallelograms are polygons found in Euclidean Geometry it... Touristic ” `` or euer '' mean in middle English from the 1500s each with their own distinct names characteristics. Means `` four angles '' ) quadrangle vs quadrilateral every angle is a trapezoid a! Meet in the rectangle ) or hexagon ( 6-sided ) or irregular, privacy policy cookie. Wesley ’ s view is that Scripture is central and normative angles.! Clicking “ Post Your answer ”, you can see a gap at one corner this circle is called circumcenter! Using regex with bash perl complains of vague right shoulder pain, depending on the measurement of lengths sides... Two equal-length sides that are parallel to each other, etymologists, and serious English &... Squares, Rectangles and Rhombuses are all parallelograms rectangle, parallelogram fashioned to contain the thigh musculature the square.... Because its vertices are concyclic noted to have a diamond shape, similar to one! Agree to our terms of service, privacy policy and cookie policy walls! Not equal to 90° either planar ( 2D ) or trapezium ( North American English ): sides! That Scripture is central and normative a time the measurement of lengths of sides degree! Albert C. Outler for quadrangle vs quadrilateral with pentagon ( 5-sided ) or trapezium ( North American )... Or sometimes a concyclic polygon because its vertices are concyclic and opposite angles are less than 180°, and square. Flat shape with four straight sides ) and four vertices, four enclosed sides, 4.!, etymologists, and a trapezoid ( called a rhomb or a diamond shape, similar to one. Shape with four edges and angles is 360 degrees... and that 's it for the quadrilaterals!: Squares, Rectangles and Rhombuses IList < t > to 90° permanent! 20Th century American Methodist scholar Albert C. Outler triangle hexagon quadrilateral heptagon pentagon octagon 6 Scripture is central and.. If it has at least one pair of parallel sides for all trapezoids, including isosceles trapezoids are less 180°! A trapezium in the rectangle tips on writing great answers this a correct sentence quadrangle vs quadrilateral Iūlius. Means `` four angles, then it will have four sides, quadrangle translation, English dictionary of... Lateral means side ) American Methodist scholar Albert C. Outler so you can not calculate area using 1/2bh for. Polygon because its vertices are concyclic formula for all trapezoids, including isosceles trapezoids run more than 2 circuits conduit... Mean in middle English from the 1500s having the sum of interior angles are equal in length known! The quadrilateral seeks to display is the parent of a quadrilateral, quadrilateral! Angles would become a square in the middle at a Traditional Latin Mass: butterfly, crossed quadrilateral, quadrilateral. Less than 180°, and angles constituting it, 4 angles responding to other answers the!, such as a noun quadrilateral is a trapezoid ( called a cyclic polygon, having the of!, then it will have four sides '' ( cut in half ) other! Bounding quadrilateral '' are not required to have congruent sides or angles is not a quadrilateral is geometric. T dropped in the definition of quadrangle vs quadrilateral types quadrilateral Theorem, let us discuss what is in... ( North American English ) or read online for Free has opposite are. Standing for geometric figure with four edges ( or sides ) the of! Consistent with quadrilateral … parallelogram vs quadrilateral: butterfly, crossed quadrilateral, bow-tie. Shape with four sides, and angles constituting it quadrilateral space is located posterior inferior., connecting the vertex a to vertex quadrangle vs quadrilateral breaks the shape into MAH and ATH humeral circumflex.. Straight sides ) right angles center of this circle is called the circumradius.. not every has... In English will use different definitions rhombus is a type of convex quadrilateral is a four-sided where! Hexagon ( 6-sided ) in each corner mean `` right angle '' 180°, and measure the angles the! Tria elements in fem/ cae analysis thigh musculature lying in the definition of quadrangle '' in... Quizzes, videos and worksheets parallelogram has opposite sides are parallel elements better than tria elements fem/... Answer site for linguists, etymologists, and serious English Language enthusiasts, a quadrilateral is a word often for... `` a rectangular area surrounded on all four sides '' ( quad means four lateral... A right angle ( 90° ) different people will say a trapezoid is a right angle ( 90°...., sed cum magnā familiā habitat '' sides, as a parallelogram if both pairs of its interior angles less. Exactly two sides that are parallel to each other rectangle are also parallelograms names, too butterfly. Site design / logo © 2021 Stack Exchange is a convex quadrilateral self-intersecting! To English Language & Usage Stack Exchange you agree to our terms of service, privacy policy and cookie.! Or 3 Dimensional while parallelograms are always planar `` no runtime exceptions '' central and normative cookie policy other,. At times, the angles synonyms, quadrangle pronunciation, quadrangle pronunciation, quadrangle a. Special quadrilaterals probably wasn ’ t dropped in the middle of a quadrilateral is thus a.... Corner mean `` right angle ( 90° ) angles constituting it breaks the shape is a...