The diameter of a right circular cylinder is increasing at a rate of 4 cm/sec, while the height is decreasing at a rate of 3 cm/sec. At what rate is the radius changing when the diameter is 10 cm?
This is a Related Rates practice problem I'm struggling with. I understand that $\frac{dd}{dt} = 4$ and that $\frac{dh}{dt} = -3$ ... but I don't know how to solve the problem with a missing height value AND a missing volume? What do I susbsitute?