Across
- 1. (of an angle) less than 90 degrees
- 4. of an angle, between 90 and 180 degrees
- 8. (of a triangle) having two sides of equal length
- 9. coinciding when superimposed
- 10. having a common boundary or edge
- 11. intersecting at or forming right angles
- 12. the extent of a two-dimensional surface within a boundary
Down
- 2. the length of the closed curve of a circle
- 3. two angles whose sum is a right angle
- 5. the side of a right triangle opposite the right angle
- 6. the length of a straight line through the center of a circle
- 7. the space between two lines or planes that intersect