A cuboid has a diagonal of length 9 cm and a square base of side 4cm. What is its height?

Answer 1

Find the diagonal of the base using Pythagoras, call it d
Let the height of the cuboid be h.

Then the diagonal of the base and the height form a right-angled
triangle with hypotenuse 9.
that is: h^2 + d^2 = 9^2 , you have d^2 from the first part, solve for h