3*4.7/5280 - 2*9.0/5280 = 3*(r-sqrt(r^2-2^2)) - 2*(r-sqrt(r^2 - 3^2))

Uh oh! Wolfram|Alpha doesn't run without JavaScript.

Please enable JavaScript. If you don't know how, you can find instructionshere.Once you've done that, refresh this page to start using Wolfram|Alpha.