We are going to base the answer off of the y=mx+b form where m represents slope and b represents the y-intercept.
First, we know that b must be -1 because the line hits the y-axis when y is -1 So this leaves us with either the first or second choice
Then we choose two points to find the slope. I am using (0,-1) and (1,2). If you count the boxes, the y-value increases by 3 as the x-value increases by 1. So the slope is 3/1 or 3.
