Geometry Crossword Puzzle

3. A line segment joining a vertex to the midpoint of the opposite side.
5. Straight one-dimensional figure that has no thickness and extends endlessly.
6. Line segment through a vertex and perpendicular to a line containing the base.
9. Statement that is opposite if another operation.
11. A proposition or statement that is demonstrated.
12. Width X Height.
14. Pair of adjacent angles formed when two lines intersect each other.
16. Total length of the sides of a two-dimensional shape.
18. 90 degree angle.
19. Measured in degrees.

1. Center of triangle where bisectors of the interior angles intersect.
2. Ten-sided polygon.
4. Angle that measures less than 90 degrees.
7. Middle point of a line segment.
8. Flat, two-dimensional surface that extends indefinitely.
10. Shape with 4 equal sides and 4 90 degree angles.
13. Shape with 2 pairs of equal length sides that are adjacent to each other.
15. Statements that are assumed to be true without proof.
16. A location.
17. A part of a line that has a fixed starting point but no end point.