A circus tent is in the shape of a square pyramid. Each edge of the square base is 20 m and its slant height is 13.5 m. Find the height of the tent. Round the answer to the nearest tenth.(1 point)

14.8 cm
16.8 m
24.1 cm
9.1 m

1 answer

To find the height of the square pyramid (circus tent), we can use the Pythagorean theorem.

  1. The base of the pyramid is a square with each edge measuring 20 m. This means the half-length of the base, which we will call \(a\), is: \[ a = \frac{20}{2} = 10 \text{ m} \]

  2. The slant height of the pyramid (the height of the triangular face) is given as 13.5 m. We will denote this slant height as \(l\).

  3. Let's denote the height of the pyramid as \(h\).

According to the Pythagorean theorem, we can relate the height, the half-base, and the slant height as follows: \[ l^2 = h^2 + a^2 \]

Substituting in the known values: \[ (13.5)^2 = h^2 + (10)^2 \]

Calculating \(13.5^2\) and \(10^2\): \[ 182.25 = h^2 + 100 \]

Now, isolate \(h^2\): \[ h^2 = 182.25 - 100 \] \[ h^2 = 82.25 \]

Taking the square root to find \(h\): \[ h = \sqrt{82.25} \approx 9.065 \]

Rounding to the nearest tenth: \[ h \approx 9.1 \text{ m} \]

Thus, the height of the tent is 9.1 m.