Make r the subject of formula t=2πr(r+h)
t=2πr(r+h)
t = 2πr^2 + 2πhr
2πr^2 + 2πhr - t = 0
this is a quadratic in r, where a = 2π , b = 2πh and c = -t
r = (-2πh ± √(4π^2h^2 - 4(2π)(-t) )/(4π)
see if you can simplify that
explain in detail
I don't understand
I don understand
r=A-h
so you will be re-arranging to get r all by itself...
it is a wee bit tricky due to the r inside and outside of the bracket.
Do you usually treat it like a quadratic and factor it?
Because that would be a lovely solution : )