Question

A 20-ft ladder is placed against the side of a house. The bottom of the ladder is 12 feet from the house. How high up will the ladder reach on the wall?

Answer 1

Use Pythagorean theorem to solve this problem.

$a^{2}\ +\ b^{2}=c^{2}\\\\b^{2}=20^{2}-12^{2}\\\\b^{2}=400-144\\\\\sqrt{b^{2}} =\sqrt{256}\\\\b=16\ ft$

The ladder will reach 16 ft up the wall.