## Thinking Mathematically (6th Edition)

$x=-15$
$\frac{-3}{8}$=$\frac{x}{40}$ Step 1: Cross Multiply $8\times x$=$-3\times40$ $8x=-120$ Step 2: Divide by 8 on both sides $8x\div8$=$-120\div8$ $x=-15$ Answer: $x=-15$