I'm having trouble with b. any suggestions on how to get started without having the equation for f'(x) ?
You don't need it.
Your graph shows the derivative of , or the slope of at every point on the closed interval [-3, 7]
Your graph shows that at , , or that the slope at is 1.
You also know that the function takes on the value
Plug these two known facts into the equation , find the intercept and you're done.