Question

Guys i need help. My niece has come over my house and she need help with this question any help?

Loves from KIM.

A ladder that is 21 feet long is propped against a building. The bottom of the ladder was placed 4 feet from the base of the building. How high up on the building does the ladder reach? Round the answer to the nearest tenth of a foot.
4.1 feet
17.0 feet
20.6 feet
21.4 feet

Answer 1

C

Explanation:

I took test on Edg

Answer 2

using the Pythagoras theorem,

21²=4²+height²
441=16+height²
425=height²
height=√425=20.6

The ladder reaches a height of 20.6 ft on the building.