Geometry Terms - chapter 4

Question 1

acute triangle

Answer 1

a triangle with three acute angles

Question 2

auxiliary line

Answer 2

a line drawn in a figure to aid in a proof

Question 3

base of an isosceles triangle

Answer 3

the side opposite the vertex angle

Question 4

base angle of an isosceles triangle

Answer 4

one of the two angles that have the base of the triangle as a side

Question 5

congruent polygons

Answer 5

polygons whose corresponding sides and angles are congruent

Question 6

coordinate proof

Answer 6

a style of proof that uses coordinate geometry and algebra

Question 7

corollary

Answer 7

a theorem whose proof follows directly from another theorem

Question 8

corresponding angles of polygons

Answer 8

angles in the same position in two different polygons that have the same number of angles

Question 9

corresponding sides of polygons

Answer 9

sides in the same position in two different polygons that have the same number of sides

Question 10

CPCTC

Answer 10

abbreviation for “Corresponding Parts of Congruent Triangles are Congruent”

Question 11

dilation

Answer 11

a transformation in which the lines connecting every point P with its image P’ all intersect at a point C, known as the center of dilation, and CP’/CP is the same for every point P

Question 12

equiangular triangle

Answer 12

a triangle with three congruent angles

Question 13

equilateral triangle

Answer 13

a triangle with three congruent sides

Question 14

exterior of a figure

Answer 14

the set of all points outside the figure

Question 15

exterior angle of a polygon

Answer 15

an angle formed by one side of a polygon and the extension of an adjacent side

Question 16

included angle

Answer 16

the angle formed by two adjacent sides of a polygon

Question 17

included side

Answer 17

the common side of two consecutive angles of a polygon

Question 18

interior of a figure

Answer 18

the set of all points inside the figure

Question 19

interior angle

Answer 19

an angle formed by two sides of a polygon that have a common vertex

Question 20

isosceles triangle

Answer 20

a triangle with at least two congruent sides

Question 21

isometry

Answer 21

a transformation that does not change the size or shape of a figure

Question 22

legs of an isosceles triangle

Answer 22

the two congruent sides of the isosceles triangle

Question 23

obtuse triangle

Answer 23

a triangle with one obtuse angle

Question 24

remote interior angle

Answer 24

an interior angle of a polygon that is not adjacent to the exterior angle

Question 25

right triangle

Answer 25

a triangle with one right angle

Question 26

rigid transformation

Answer 26

a transformation that does not change the size or shape of a figure

Question 27

scalene triangle

Answer 27

a triangle with no congruent sides

Question 28

triangle rigidity

Answer 28

a property of triangles that states that if the side lengths of a triangle are fixed, the triangle can have only one shape

Question 29

vertex angle of an isosceles triangle

Answer 29

the angle formed by the legs of an isosceles triangle