| __ | 1. | acute angle | | A. | angle less than 90 degrees |
| __ | 2. | congruent | | B. | two angles with the same measure |
| __ | 3. | equilateral triangle | | C. | angle greater than 90 degrees |
| __ | 4. | obtuse angle | | D. | lines that intersect at right angles |
| __ | 5. | parallel lines | | E. | closed figure with four sides and four angles |
| __ | 6. | Parallelogram | | F. | angle exactly 90 degrees |
| __ | 7. | perpendicular lines | | G. | two lines in a plane that never intersect |
| __ | 8. | Quadrilateral | | H. | three congruent sides |
| __ | 9. | right angle | | I. | quadrilateral with both opposite sides parallel and congrue |
| __ | 10. | vertex | | J. | the point where the two rays of an angle meet |