A right triangular prism is constructed so that its height is equal to the leg length of the base.

A right triangular prism is shown. The right triangles have 2 sides with a length of x. The length of the hypotenuse is unknown. The height of the prism is x.

What expression represents the volume of the prism, in cubic units?

One-halfx3
One-halfx2 + x
2x3
2x2+ x