Answer
$y=\frac{1}{2}x-1$ or $x-2y=2$
Work Step by Step
Step 1. Given intercepts $(2,0),(0,-1)$, we can find the slope $m=\frac{0+1}{2-0}=\frac{1}{2}$.
Step 2. Using either point (2nd used here), we can write the equation as $y+1=\frac{1}{2}(x-0)$ or $y=\frac{1}{2}x-1$ or $x-2y=2$