Answer:
4.5 cm.
Step-by-step explanation:
The volume of the pyramid = 1/3 * area of the base * height.
Area of the triangle = 1/2 * base * height
= 1/2 * 14 * 8
= 56 cm^2.
So the volume of the pyramid =
84 = 1/3 * 56 * h
h = 84 / (1/3 * 56)
h = 84 * 3 / 56
= 4.5 cm.