Answer
$x=962,377$
Work Step by Step
$\frac{x}{-13}=4^6-5^7\rightarrow$ simplify
$\frac{x}{-13}=4096-78125\rightarrow$ simplify
$\frac{x}{-13}=-74029\rightarrow$ multiply both sides by -13
$\frac{x}{-13}\times-13=-74029\times-13\rightarrow$ simplify
$x=962377$