Final answer:
The expression that represents the radius of the cylinder is 2x.
Step-by-step explanation:
The volume of a cylinder is given by the formula V = πr2h, where V is the volume, r is the radius, and h is the height. In this case, the volume is given as 4x cubic units and the height is x units. We can substitute these values into the formula and solve for the radius:
4x = πr2x
Dividing both sides by πx, we get:
4/r2 = 1
Taking the reciprocal of both sides, we get:
r2/4 = 1
Multiplying both sides by 4, we get:
r2 = 4
Taking the square root of both sides, we get:
r = 2
Therefore, the expression that represents the radius of the cylinder is 2x.