Question

A 20-foot support post leans against a wall, making a 70° angle with the ground. To the nearest tenth of a foot, how far is the base of the post from the wall?

Answer 1

The following problem can be well explained by the diagram shown below:

Hence by the trigonometry of the figure use the trigonometric ratio of cos to get:

`\begin{gathered} \cos 70=(BC)/(AC)=(x)/(20) \\ x=20\cos 70 \\ x=6.8404\approx6.8 \end{gathered}`

Hence the support is 6.8 feet away from the wall.

Option A is correct.