Question

the ladder dad uses is 5m long, and he stands 3m away from the foot of the house. the ladder just reaches the roof. how tall is the wall? select an answer: 4 m 4.5 m 3.6 m 5.8 m

Explanation:

Step1: Apply Pythagorean theorem

Let the height of the wall be $h$. According to the Pythagorean theorem $a^{2}+b^{2}=c^{2}$, where the length of the ladder $c = 5m$ is the hypotenuse of the right - triangle, and the distance from the foot of the house to the base of the ladder $a = 3m$, and the height of the wall $b$ is what we want to find. So $b=\sqrt{c^{2}-a^{2}}$.

Step2: Substitute values and calculate

Substitute $c = 5$ and $a = 3$ into the formula: $b=\sqrt{5^{2}-3^{2}}=\sqrt{25 - 9}=\sqrt{16}=4$.

Answer:

4 m