Geometry words

3. any parallelogram with equal sides, including a square
6. a four sided rectangular plane
8. a quadrilateral whose four sides can be grouped into two pairs of equal-length sides that are adjacent to each other.
9. a plane figure with four equal straight sides and four right angles
10. an angle of 180°
12. they have a common side and a common vertex
13. an angle of 90°, as in a corner of a square or at the intersection of two perpendicular straight lines.
14. a flat closed shape having 4 straight sides, with one pair of parallel sides.
15. any angle greater than 90
16. a plane figure with four straight sides and four right angles, especially one with unequal adjacent sides, in contrast to a square.

1. a point on a polygon where the sides or edges of the object meet or where two rays or line segments meet
2. either of two angles whose sum is 90
4. either of two angles whose sum is 180
5. each of the pairs of opposite angles made by two intersecting lines
7. measures less than 90 degrees
11. identical in form; coinciding exactly when superimposed