| A | B |
|---|
| acute angle | a angle that measures less than 90 degrees |
| vertical angles | angles that are |
| complementary angles | two angles that add up to 90 degrees |
| congruent | to have the same size and shape |
| diameter | a line that cuts a circle in half |
| equilateral triangle | a triangle with all equal sides and angles |
| isosceles triangle | a triangle with two equal sides and angles |
| line | a line that goes out forever in both directions |
| line segment | a part of a line that start at one point and ends at another |
| obtuse angle | an angle that measures more than 90 degrees |
| obtuse triangle | and triangle that has one angle that measures more than 90 degrees |
| parallel lines | two lines that will never intersect each other |
| perpendicular lines | two lines that intersect each other to form right angles |
| plane | a flat surface that extends infinitely in all directions |
| point | an exact place |
| radius | a line that starts at the center point of a circle and goes to the side |
| ray | a line that starts at one point and goes on forever in the other direction |
| reflection | to create a mirror image by flipping a figure |
| regular polygon | a polygon that all the sides and all the angles are the same |
| right angle | an angle that is exactly 90 degrees |
| right triangle | and triangle that has an angle that measures exactly 90 degrees |
| rotation | to turn a figure |
| scalene triangle | a triangle that all the sides and angles have different measurements |
| supplementary angles | two angles that add up to 180 degrees |
| transformation | to change the position or orientation of a figure |
| translation | to slide a figure |
| transversal | a line that cuts through two parallel lines |
| vertex | and endpoint that multiple things share |
| acute triangle | a triangle that all angles are less than 90 degrees |
