Question

A ladder placed 4 feet from the base of a building. The ladder reaches a height of 12 feet. What is the length of the ladder ?

Answer 1

The schematic diagram of the problem is given below,

Note that the ladder forms the hypotenuse of the right triangle.

The length of the ladder can be obtained using the Pythagoras Theorem as follows,

`\begin{gathered} \text{Hypotenuse}^2=\text{Height}^2+\text{base}^2 \\ \text{Hypotenuse}^2=12^2+4^2 \\ \text{Hypotenuse}^2=\text{144}+\text{1}6 \\ \text{Hypotenuse}^2=\text{1}60 \\ \text{Hypotenuse}^{}=\sqrt[]{160} \\ \text{Hypotenuse}^{}\approx12.6 \end{gathered}`

Thus, the length of the ladder is 12.6 ft approximately.

So the third option is the correct choice.