solve each for x:
1. x + -5 = -10
2. x - (-17) = 23
3. x / 6 = -8
4. 3x = - 9
5. 2x + 6 = - 10
6. - 3x - 5 = - 10
7 4x - 8 = 0
8. 10x + 70 = 100