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Geometry Terms

Geometry terms, triangles/ angles

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88843192rhombusquadrilateral with all four sides congruent
88843193acute trianglea triangle with all three angles less than 90 degrees
88843194squareregular quadrilateral
88843195isosceles triangletriangle with two equal sides
88843196perimetersum of the lengths of the sides
88843197obtuse triangletraingle with one angle more than 90 degrees
88843198kitequadrilateral that has two pairs of adjacent sides the same length
88843199diagonala line segment connecting non-adjacent vertices of a polygon
88843200convexevery line segment connecting interior points that is entirely contained with the figure's interior
88843201parallelogramquadrilateral that has two pairs of opposite sides that are parallel
88843202right triangletriangle with one right (90 degree) angle
88843203rectanglequadrilateral with four right angles
88843204trapezoidquadrilateral that has one pair of opposite sides that are parallel
88843205equilateral triangletraingle with three equal sides
88843206polygona closed plane figure for which all sides are line segments
88843207scalene triangletraingle with all three sides unequal
88843208concavea shape or solid which has a "cave" in it
88843209congruentsame size and shape
90353928equiangular polygonAll of the angles equal each other
90353929regular polygonAll the sides and angles are the same
90353930vertex anglePoint at which two line segments intersect (forming an angle)
90353931basecongruent angles sharing a vertex
90353932vertexThe rays of an angle are also known as this
90353933equilateral polygonAll the sides equal each other
90353934base anglethe angle opposite one of the equilateral sides in an isoscoles triangle
94819171colinearpoints on the same line
94819172bisecta ray that divides an angle in half
94819173midpointthe center point of the line
94819174endpointa point that ends a line
94819175degreeA unit of measure for angles and arcs equivalent to 1/360 of a rotation around a circle.
94819176supplementary angletwo angles with a sum of 180 degrees
94819177complementary angletwo angles with a sum of 90 degrees
94819178right anglethe 90 degree angle
94819179obtuse angleAn angle that measures more than 90 degrees but less than 180 degrees
94819180acute anglean angle less than 90 degrees but more than 0 degrees
94819181linear pairtwo angles that share a vertex and a common side
94819182consecutiveone after the other, interior angles are supplementary
94819183quadrilaterala four-sided polygon
94819184rhombusa parallelogram with 4 congruent sides
94819185hexagona polygon with 6 sides
94819186pentagona five-sided polygon
94819187octagonA polygon with 8 sides
94819188parallelLines that stay the same distance apart and never meet.
94819189perpendicularintersecting at or forming right angles
110456567pointto indicate a location on a line or plane
110456568linea straight, continuous arrangement of many points
110459660planea flat surface that extends infinitely in all directions
110459661coplanarpoints on the same plane
110459662line segmenta line with two endpoints
110459663rayan endpoint with a continuous line of infinite points
110459664angletwo noncollinear rays having a common endpoint
110459665sidescongruent angles sharing a vertex
110459666segment addition postulateAB + BC = AC
110459667angle addition postulate
110459668consecutive anglesangles that share one side in common
110459669consecutive verticesin a polygon two vertices that are endpoints of the same line
110459670consecutive sidessides in a polygon that are connected by a vertex
110459671correspondingagreeing in amount, magnitude, or degree
110459672equilateralall sides are congruent
110459673equiangularhaving all angles equal
110459674regularangles and sides are congruent
110459675angle bisectorCuts in half
111706108lega side of a right triangle that include the 90 degree angle
111706109assumption...
111706110statementa message that is stated or declared
111706111reasonthink logically
111706112given...
111706113reflexiveevery triangle is congruent to itself
111706114polyhedraA three dimensional shape with flat surfaces, no holes, straight edges
111706115tetrahedroncomposed of four equilateral triangles, each three of which meet in a point
111706116cubea three-dimensional shape with six square or rectangular sides
111706117octahedronan eight-sided solid figure
111706118icosahedrona regular polyhedron with 20 triangular faces is called a(n)
111706119irregular polyhedrapolygons that are composed of elements that are not all equal.
111706120facea polygonal region of a surface
111706121sidecongruent angles sharing a vertex
111706122edgea segment that helps to make up a face
111866918vertical anglesare congruent and are equal to each other
111866919heptagonpolygon with 7 sides
111866920nonagonpolygon with 9 sides
111866921decagonpolygon with 10 sides
111866922dodecagonpolygon with 12 sides
111866923transversalline that intersects two or more other coplanar lines
111866924alternate interior anglesangles between 2 lines and on opposite sides of a transversal
111866925alternate exterior anglesAngles that lie outside a pair of lines and on opposite sides of a transversal.
111866926corresponding anglesangles in the same place on different lines
111866927perpendicular bisectorA line that is perpendicular to a segment at its midpoint.

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