Marco needs to climb up to the roof of his house. He placed his ladder so that the bottom of the ladder was 4 feet away from the wall. If his ladder was 13 feet long, how high up was the
top of the ladder against the wall of the house? Round your answer to the nearest tenth.

12.4 feet

Step-by-step explanation:

A ladder placed against the wall forms a right angle triangle

Hypotenuse ² = opposite ² + adjacent ²

Hypotenuse = 13 feet

Opposite = 4 feet

Adjacent = x

Hypotenuse ² = opposite ² + adjacent ²

13² = 4² + x²

169 = 16 + x²

169 - 16 = x²

153 = x²

Find the square root of both sides

√153 = √x²

12.369316876852 = x

x = 12.4 feet

Adjacent = x = 12.4 feet