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
In our case, we have V=12, and b=3. So we have the following equation
So, we should find the value of h from this equation. To do, we simply divide both sides by 3, so we get
so the height of the pyramid is 4 feet.