## Algebra: A Combined Approach (4th Edition)

The graph has a vertical line with x-intercept 2. Find pair solutions of x=2. We let (x1,y1)=(2,0) and (x2,y2)=(2,1) $m=\frac{1-0}{2-2}=\frac{1}{0}=0$ Since $\frac{1}{0}$ is undefined, the slope of x=2 is undefined