Answer:
Step-by-step explanation:
1) a) 15x = 12x + 15 {Alternate interior angles}
b) 15x - 12x = 15 {Subtract 12x from both sides}
3x = 15
x = 15/3
x = 5
c) Alternate interior angles
2) a) 3x + 10 + 3x - 28 = 180 {co- interior angles are supplementary}
b) 6x - 18 = 180 { Combine like terms}
6x = 180 + 18
6x = 198
x = 198/6
x = 33
c) co- interior angles are supplementary
3) a) 7x + 9 + 5x +3 = 180
b) 12x + 12 = 180
12x = 180 - 12
12x = 168
x = 168/12
x = 14
c) linear pair
4) a) 12x - 18 = 8x + 10
b) 12x - 8x - 18 = 10
4x - 18 = 10
4x = 10 +18
4x = 28
x = 28/4
x = 7
c) Vertically opposite angles are equal.
