16) -9x - 13 = -103\n18) -10 = -10 + 7m\n20) $\frac{m}{9}-1=-2$

Explanation:

Step1: Solve -9x - 13 = -103

Add 13 to both sides. $-9x-13 + 13=-103 + 13$ $-9x=-90$ Then divide both sides by -9. $x=\frac{-90}{-9}=10$

Step2: Solve -10=-10 + 7m

Add 10 to both sides. $-10+10=-10 + 10+7m$ $0 = 7m$ Divide both sides by 7. $m = 0$

Step3: Solve $\frac{m}{9}-1=-2$

Add 1 to both sides. $\frac{m}{9}-1 + 1=-2 + 1$ $\frac{m}{9}=-1$ Multiply both sides by 9. $m=-9$

Answer:

For -9x - 13 = -103, x = 10; for -10=-10 + 7m, m = 0; for $\frac{m}{9}-1=-2$, m=-9