Asked by Anonymous

Oil spilled from a ruptured tanker spreads in a circle whose area increases at a constant rate of 7.5 mi2/hr. How rapidly is radius of the spill increasing when the area is 10 mi^2?
Answered by Reiny
A = πr^2
dA/dt = 2πr dr/dt

when A = 10
πr^2 = 10
r^2 = 10/π
r = √(10/π)

you now have r and dr/dt, so just plug in and push buttons on your calculator
Answered by John
0.66905
Answered by NIG
YO stupidddd Reiny. did u even go to svchoolllll! LIL PEEEEEEEPP