Assume that x and y are both differentiable functions of t and find the required values of dy/dt and dx/dt. xy = 2 (a) Find dy/dt, given x = 4 and dx/dt = 12. dy/ dt = (b) Find dx/dt, given x = 1 and dy/dt = -5. dx/dt =A point is moving along the graph of the given function at the rate dx/dt. Find dy/dt for the given values of x. y = 4x- + 9; dx = 5 centimeters per second dt (a) X = - dy cm/sec dt (b ) x = 0 dy = cm/sec dt (c) X=1 dy cm/sec dtThe radius r of a circle is increasing at a rate of 7 centimeters per minute. Find the rate of change of the area when r = 31 centimeters. cm2/min