MY NOTES ASK YOUR TEACHER PRACTIC Assume that x and y are both differentiable functions of t and find the required values of dy/dt and dx/dt. x2 + 12 = 225 (a) Find dy/dt, when x = 9, y = 12 given that dx/dt = 8. (b) Find dx/dt, when x = 12, y = 9, given that dy/dt = -3. Need Help? Read It Watch It 4. [-/2 Points] DETAILS LARAPCALC10 2.8.009. MY NOTES ASK YOUR TEACHER PRACTICE A spherical balloon is inflated with gas at a rate of 14 cubic feet per minute. How fast is the radius of the balloon changing at the instant the radius is 1 foot and 4 feet? (a) 1 foot ft/min (b) 4 feet ft/min Need Help? Read It Watch It