Answer
V=$\frac{4}{3}$$\pi$($x^{2}$+6x+9)
Work Step by Step
If V=$\frac{4}{3}$$\pi$$r^{2}$ gives the volume of a sphere with radius r, to find the volume of a sphere with radius x+3 we simply plug in x+3 for r
If r=x+3, then
V=$\frac{4}{3}$$\pi$$(x+3)^{2}$
We then apply the rule that states that
$(a+b)^{2}$=$a^{2}$+2ab+$b^{2}$ and set a=x and b=3
So
V=$\frac{4}{3}$$\pi$($x^{2}$+2(x)(3)+$3^{2})$
V=$\frac{4}{3}$$\pi$($x^{2}$+6x+9)
