| __ | 1. | Acute | | A. | A closed shape with four sides. |
| __ | 2. | Equilateral | | B. | A triangle with 2 equal sides and angles. |
| __ | 3. | Isosceles | | C. | A triangle with 3 different side lengths. |
| __ | 4. | Obtuse | | D. | A triangle with 3 equal sides and angles. |
| __ | 5. | Quadrilateral | | E. | A triangle with angles less that 90º. |
| __ | 6. | Rectangle | | F. | A triangle with an angle more than 90º but less than 180º. |
| __ | 7. | Right | | G. | a meeting point of two lines that form an angle |
| __ | 8. | Scalene | | H. | All sides are the same. All angles are right angles. |
| __ | 9. | Square | | I. | A triangle with a right angle. Must have box indicating righ |
| __ | 10. | Vertex | | J. | Opposite sides are parallel. All angles are right angles. |
| __ | 21. | 9 | | A. | Nonagon |
| __ | 22. | 10 | | B. | Decagon |
| __ | 23. | Concave | | C. | Undecagon, an angle greater than 180 degrees (but less than |
| __ | 24. | Convex | | D. | An angle that measures 180 degrees, a straight line. |
| __ | 25. | Irregular Polygon | | E. | A polygon with a reflex angle, curved inward, creating a hol |
| __ | 26. | reflex angle | | F. | A polygon with no reflex angle, all vertices appear to be pu |
| __ | 27. | Regular Polygons | | G. | Same sides, same lengths. |
| __ | 28. | straight angle | | H. | The sides are different lengths. |