Answer:
19.21 units
Step-by-step explanation:
The base of the square pyramid is 12 units.
The vertical height of the square pyramid is 15 units.
(A square pyramid is shown in the diagram. The dash lines represents the vertical height)
The problem, therefore, represents a right angled triangle.
The adjacent and opposite are the length of base and vertical height of the pyramid respectively (12 units and 15 units).
We need to find the hypotenuse (length of the triangular face).
Applying Pythagoras theorem:
[tex]hyp^2 = opp^2 + adj^2[/tex]
[tex]hyp^2 = 12^2 + 15^2\\\\\\hyp^2 = 144 + 225 = 369\\\\\\hyp = \sqrt{369}\\ \\\\hyp = 19.21 units[/tex]
Therefore, the length of the triangular faces is 19.21 units.
