Question

A 72 foot ladder is leaning against a building. The base of the ladder is 5 feet from the building. How high up the building does the ladder reach? Round your answer to the nearest tenth

Answer 1

The ladder reaches 71.8ft high from the building

Explanation:

This problem can be thought of as a right triangle

to calculate the height we will use Pythagoras

we will represent the ladder with the hypotenuse

h = hypotenuse = 72ft

l1 = leg 1 = 5ft

l2 = leg 2

h² = l1² + l2²

we replace with the known values

(72ft)² = (5ft)² + (l2)²

5184ft² = 25ft² + (l2)²

5184ft² - 25ft² = l2²

5159ft² = l2²

√(5159ft²) = l2

71.826ft = l2

round to the neatest tenth

l2 = 71.826ft = 71.8ft

The ladder reaches 71.8ft high from the building