a Find the slope of the tangent line to the parabola y x 7x at the point 3 12 by using the following parameters i The tangent line to the curve y f x at the point P a f a is the line through P with slope m lim x a m ii The expression of slope is m lim h 0 y m b Find an equation of the tangent line in part a 10 5 20 c Graph the parabola and the tangent line As a check on your work zoom in toward the point 3 12 until the parabola and the tangent line are indistinguishable y y y 5 5 5 y 10 15 10 10 20 f a h f a h V 5 10 X f x f a x a 10 provided that this limit exists X 1 10 5 5 SE 10 15 5 X