the graph of the function f x x2 x 12 a Find the equation of the secant line joining the points 2 6 and 4 0 b Use the Mean Value Theorem to determine a point c in the interval 2 4 such that the tangent line at c is parallel to the secant i c Find the equation of the tangent line through c d Use a graphing utility to graph f the secant line and the tangent line 10 06 2 10 8 6 4 2 ad Help Read to d 2 2 4 19 12 2 7 2 6 8 10 10 10 86 10 149 T 2 of