Vertical, Horizontal, Inclined. (c) Relative positions of two or more lines: 1 Inclined. (d) Relation between angles: (1) Complementary, (4) Complementary Adjacent, (2) Supplementary, (5) Supplementary Adjacent, (3) Adjacent, (6) Vertical. 11. Plane Surface or Plane. Polygon, Triangle. Plane Figure, 12. Triangle. (a) Kinds: (1) Equilateral, (4) Equiangular, (6) Obtuse, (1) Equal, (4) Mutually Equiangular, (2) Equivalent, (5) Mutually Equilateral. 1. Through two given points only one straight line can be drawn. 2. A straight line is the shortest line between two points. 3. Two magnitudes equal to the same magnitude or equal magnitudes are equal. 4. If the same operation be performed on equals, the results are equal. 5. If the same operation be performed on unequals, the results are unequal in the same sense. 6. If unequals be subtracted from equals, the results are unequal in the inverse sense. 7. The whole is greater than any of its parts. 8. The whole equals the sum of its parts. 9. If, of three quantities, the first is greater than the second, and the second is greater than the third, then the first is greater than the third. 10. If the greater of two magnitudes is continuously decreasing, and the smaller continuously increasing, once, and only once, will the magnitudes be equal. 11. If two plane figures can be made to coincide by super position, the figures are equal. |