Question

Construct a square based pyramid of volume 216cm3. What are the dimensions?

Answer 1

let the base be x by x cm
let the height be y xm

Volume = (1/3) r^2 h = 216
r^2 h = 648

h = 648/r^2

pick any r, let's say r = 10, then h = 648/100 = 6.48 cm
pick x = 12 cm, then h = 648/144 = 4.5 cm

As you can see, there is not enough information.
as it stands the dimensions could be anything that satisfies our above equation