Recall that we can do the following picture
We want to find the height of this pyramid and are told the volume of the pyramid. Recall that the volume of a square pyramid of height h and base length b is given by the formula
[tex]V=\frac{1}{3}b^2\cdot h[/tex]In our case, we have V=12, and b=3. So we have the following equation
[tex]12=\frac{1}{3}\cdot3^2\cdot h=3\cdot h[/tex]So, we should find the value of h from this equation. To do, we simply divide both sides by 3, so we get
[tex]h=\frac{12}{3}=4[/tex]so the height of the pyramid is 4 feet.