#### Answer

n=20

#### Work Step by Step

To solve for n in the equation $\frac{-4}{9}$=$\frac{n}{-45}$, we first cross multiply to get the equation
(-4)(-45)=(n)(9)
180=9n
Then, to solve for n, we'll divide by 9 on both sides of the equation
$\frac{180}{9}$=$\frac{9n}{9}$
20=n