Geometry

5. A line segment between the center and a point on the circle or sphere.
7. A pair of triangles have exactly the same three sides and exactly the same three angles.
8. Two distinct coplanar lines that do not intersect.
9. An angle that has measure less than 90°.
11. A quadrilateral with four congruent angles (all 90°).
16. Two acute angles that add up to 90°.
17. Two lines at a 90° angle to each other.
18. An angle that has measure more than 90° and less than 180°.
19. An angle in a circle with vertex on the circle itself.
20. A quadrilateral with four congruent sides and four congruent angles (all 90°).

1. A quadrilateral with two pairs of parallel sides.
2. A line segment between two points on the circle or sphere which passes through the center.
3. Two angles that add up to 180°.
4. The distance around the outside of a circle.
6. A three-dimensional geometric figure with parallel congruent bases.
10. Angle formed by the angles in matching corners when two lines are crossed by another line (which is called the Transversal).
12. A quadrilateral which has one parallel pair of opposite sides and one non-parallel pair of opposite sides.
13. A triangle with three congruent sides.
14. A triangle for which all three sides have different lengths.
15. A parallelogram with four congruent sides.