Answer:
16units
Explanation:
Given the length of the base of a square based pyramid as 12 units and the vertical height of the pyramid to be 15units, the height of one of its triangular faces can be gotten by using the pythagoras theorem.
Let the height of one of the triangular sides be s (it is also the slant height of the pyramid)
The vertical height of the pyramid to be h = 15units
The base of the right angled trangle will be half of the length of the base = 12/2 r = 6 units
According to the pythagoras theorem; s² = h² + r²
Substituting the given values into the formula we will have;
s² = 15² + 6²
s² = 225 + 36
s = 261
s = 16.16 units
s ≈ 16units (to the nearest tenth)
Hence the length of the height of one of the triangular faces is 16units