#### Answer

8, $-\frac{3}{2}$

#### Work Step by Step

a. We are given the equation $\frac{x}{8}=-4$. In order to solve, we need to multiply both sides by 8, which will simplify the left side to $\frac{x}{8}\times8=x$. Doing so will allow us to isolate the variable on one side.
b. We are given the equation $-6=-\frac{2}{3}k$. In order to solve, we need to multiply both sides by $-\frac{3}{2}$, which will simplify the right side to $-\frac{2}{3}k\times-\frac{3}{2}=k$. Doing so will allow us to isolate the variable on one side.