| A | B |
|---|
| acute angle | an angle which measures less than 90 degress |
| obtuse angle | an angle which measures more than 90 degrees |
| scalene triangle | a triangle with no equal sides |
| isosceles triangle | a triangle with two equal sides |
| equilateral triangle | a triangle with three equal sides |
| right triangle | a triangle with a right angle |
| quadrilateral | a polygon with four sides |
| square | a parallelogram with four equal sides and four right angles |
| rhombus | a parallelogram with four equal sides and no right angles |
| trapezoid | a quadrilateral with one set of parallel lines |
| rectangle | a parallelogram with two sets of equal sides and four right angles |
| parallelogram | a quadrilateral with two sets of parallel sides and no right angles |
| hypotenuse | the side across from the right angle in a right triangle |
| polygon | a closed plane figure with straight sides |
| line segment | part of a line with a definite beginning and end |
| parallel lines | lines which never intersect |
| perpendicular lines | lines which intersect at a right angle |
| right angle | an angle which measures exactly 90 degrees |
| diameter | a line in a circle which measure from side to side through the center |
