Calculate Pyramid Height: 150m Sides and 120m Base Using Geometry

Question

The Egyptians decided to build another pyramid that looks like an isosceles triangle when viewed from the side.

Each side of the pyramid measures 150 m, while the base measures 120 m.

What is the height of the pyramid?

150150150120120120150150150

Video Solution

Solution Steps

00:00 What is the height of the pyramid?
00:03 In an isosceles triangle, the height is also a median
00:06 Let's mark half the side length as X
00:10 Let's substitute the side value according to the given data and solve
00:16 We'll use the Pythagorean theorem to find height H
00:22 Let's substitute the value of X
00:26 Let's isolate height H
00:37 And this is the solution to the question

Step-by-Step Solution

Since the height divides the base into two equal parts, each part will be called X

We begin by calculating X:120:2=60 120:2=60

We then are able to calculate the height of the pyramid using the Pythagorean theorem:

X2+H2=1502 X^2+H^2=150^2

We insert the corresponding data:

602+h2=1502 60^2+h^2=150^2

Finally we extract the root: h=1502602=225003600=18900 h=\sqrt{150^2-60^2}=\sqrt{22500-3600}=\sqrt{18900}

h=3021 h=30\sqrt{21}

Answer

3021 30\sqrt{21} m