For y=2x+125, the slope is 2, which means that the total will increase by 2, and the y-intercept is 125, and that is the starting value. So, y=2x+125 goes with the second choice on the right. For y=1/2x+125 means that 125 is still the starting value but instead of the total amount increasing by 2, it is divided by 2 and goes with the first choice on the right. For y=125x+2, the slope is 125 and 2 is the y-intercept, so the answer is the last one on the right.
