Look at the face of the pyramid facing you. The length of the base of this pyramid is 82 m; half of that is 41 m.
If you were to draw a straight vertical line through the vertex of the pyramid, the bottom of this line would be at the very center of the base and also be 41 in perpendicular distance from any of the edges of the base of this pyramid.
Let the height of the pyramid be y, as measured upward from the center of the base of the pyramid. This center is, as before, 41 m from any side of the pyramid base, a horiz. distance.
Then, tan 52 deg = y / 41 m, and so y = height of pyramid =
