Chapter 1: Foundations of Geometry

12345678910111213141516171819
Across
  1. 4. lines whose intersection is a single point
  2. 8. lines that are NOT on the same plane
  3. 9. through any three noncollinear points there is exactly one ____
  4. 10. Greek mathematician considered to be the father of geometry
  5. 12. objects in a set
  6. 13. points that lie on the same line
  7. 15. the type of angle that measures less than 90 degrees
  8. 16. the type of angle that measures 180 degrees
  9. 19. if two planes intersect then they intersect in exactly one ____
Down
  1. 1. statements that are shown to be true by a proof
  2. 2. a set containing no elements
  3. 3. most angles are named with 3 letters in which the middle letter is always the ____ of the angle
  4. 5. the type of angle that measures between 90 and 180 degrees
  5. 6. the distance around a circle
  6. 7. planes that do not intersect
  7. 11. sets that have nothing in common
  8. 14. the union of a half-line and its origin
  9. 16. four noncoplanar points determine _____
  10. 17. the union of two distinct rays with a common endpoint
  11. 18. consists of two endpoints and all the points between them