Use the image to answer the question.

An illustration shows a square pyramid with labeled parts. The left, front, and right faces of the pyramid and base are visible. The back face is not visible, but its position is indicated by a dashed line. The back base edge is not visible, but its position is indicated by a dashed line. The left base edge is labeled a. The back left lateral edge is labeled e. A dotted line extends from the interior of the vertex straight down to the center of the base and is labeled h. A right angle is indicated where the dotted height line meets the base. Another dotted line extends from the center of the base where the height line meets to the center of the right base edge and is labeled r. A dotted line extends from the right base edge straight up the center of the right face of the prism and meets the height line at the vertex. The dotted slant height line is labeled s.

For the square pyramid, the lateral edge length, e
, is 25 in., and the slant height, s
, is 24 in. Find the height of the pyramid, h
. Round the answer to the nearest whole number. Hint: Before finding the length of h
, you will first need to find the length of r
.

(1 point)
The height of the square pyramid is
in.
Remaining Attempts : 3

1 answer

To find the height \( h \) of the square pyramid, we will first determine the length of \( r \), which is the distance from the center of the base to the midpoint of the base edge.

Given that the lateral edge length \( e = 25 \) in and the slant height \( s = 24 \) in, we can visualize a right triangle formed by the height \( h \), the slant height \( s \), and the distance \( r \).

  1. Since the pyramid's base is a square, the distance \( r \) (half the length of one side of the base) can be calculated using the Pythagorean theorem: \[ e^2 = h^2 + r^2 \] We can express \( r \) in terms of the edge length of the base \( a \) as: \[ r = \frac{a}{2} \]

  2. Now we know \( s^2 = h^2 + r^2 \). So we can express \( r \) in terms of \( s \) and \( h \): \[ r = \sqrt{s^2 - h^2} \]

  3. Since we need \( r \) in terms of \( h \) to solve for \( h \) eventually, we notice that from the information available, we don't have the side length \( a \), but we can calculate \( r \) using a derived relationship.

  4. Since we are given that: \[ e^2 = h^2 + r^2 \tag{1} \] And also since we earlier stated that: \[ r = \sqrt{s^2 - h^2} \tag{2} \]

Setting up these equations, we can formulate it based on \( e = 25 \) and \( s = 24 \):

Using equation (1): \[ 25^2 = h^2 + r^2 \implies 625 = h^2 + r^2 \] Also using equation (2): \[ r^2 = s^2 - h^2 \implies r^2 = 24^2 - h^2 \implies r^2 = 576 - h^2 \]

Substituting \( r^2 \) into the equation we have: \[ 625 = h^2 + (576 - h^2) \] This will simplify: \[ 625 = 576 + h^2 \implies h^2 = 625 - 576 = 49 \implies h = \sqrt{49} = 7 \]

Thus, the height of the square pyramid \( h \) is: \[ \boxed{7} \text{ in.} \]