Math terms

123456789101112131415
Across
  1. 3. Combines into a sum
  2. 6. In alignment
  3. 9. 3-sided figure
  4. 10. Half the diameter
  5. 11. Length x width x height
  6. 12. Not nice
  7. 14. When 2 lines meet
  8. 15. Distance across a circle
Down
  1. 1. 4-sided figure
  2. 2. Expression of 2 terms with the same value
  3. 4. An amount of money
  4. 5. Intersecting at a right angle
  5. 7. Perimeter of a circle
  6. 8. Middle of the pack
  7. 13. Length x width