| Down |
| 1. | neutral; avoids limitations of time or place |
| 2. | straight; extends infinitely in one direction; length, no width or thickness |
| 3. | flat, extends infinitely in two dimensions |
| 5. | if 2 planes intersect, then their intersection is exactly one line |
| 6. | to the point; no ambiguous or vague language |
| 9. | coplanar lines that do not intersect |
| 10. | a line contains 2 points; a plane contains 3 noncollinear points; space contains 4 noncoplanar points |
| 11. | planes in space that do not intersect |
| 13. | process of justifying a theorem |
| 16. | set that contains no elements |
| 17. | a system of definitions, postulates, and theorems that is built in a logical progression |
| 18. | lines that intersect at a single point |
| 21. | lines that lie in the same plane |
| 22. | assumed to be true |
| 24. | lines that are not coplanar |
| 25. | How many points are required for something to be noncollinear |
| 26. | model based on 5 incidence postulates |
| 27. | points that lie in the same plane |
| 28. | refers to processes that require two sets |
| 31. | what makes a good geometry |
| 32. | denoted by "U" |
| 33. | interrelation or sequence of facts or events when seen as inevitable or predictable |
| 34. | good grammar, good sentence, only necessary words |
| 37. | repeat the pattern established by the last 3 elements |
| 39. | sets with the exact same elements |
| 40. | using words previously defined or commonly accepted as undefined |
| 41. | another name for a postulate |