He is incorrect is does pass through the point (0,1) but the slope is not 1/2 it is 2. I know this because the formula to find slope is rise over run. The rise is 2 and the run, moving horizontally, is 1. 2/1 is 2 so to make the slope 1/2 you have to make the rise 1 and the run 2. So he needs to not graph the (1,3) point but instead the other point other than (0,1) that needs to be graphed is (2,2).