C. Since the baby is born weighing 7 pounds, at 0 months he will weigh 7 pounds. This tells us that the y-intercept will be seven. And since the baby is gaining 1.5 pounds every month, this means that the slope will be 1.5 and m will be the x of our y = mx + b equation. For part B, we simply plug in 7 to m and solve by multiplying 1.5 and 7 to get 10.5, then adding 7 to get 17.5.
