Question

The volume of a cylinder is 47x3 cubic units and its height is x units.
Which expression represents the radius of the cylinder, in units?
2x
HERE
4x
22x2
42x²

Answer 1

The volume of a cylinder is given by

$V=\pi hr^2$

Solving for the radius, we have

$r=\sqrt{\dfrac{V}{\pi h}}$

We are given

$V=47x^3,\quad h=x$

So the radius would be

$r=\sqrt{\dfrac{47x^3}{\pi x}}=\sqrt{\dfrac{47x^2}{\pi}}$