Question

A boat is heading towards a lighthouse, where Dalvin is watching from a vertical distance of 138 feet above the water. Round your answer to the nearest tenth of a foot if necessary.

Answer 1

To find the first distance we use:

$\begin{gathered} tan13=\frac{138ft}{x} \\ x=\frac{138ft}{tan13º} \\ x=\frac{138ft}{0.23} \\ x=\text{ 600ft} \end{gathered}$

For the second distance, we change 13º to 45º and 77º to 45º as well.

So:

$\begin{gathered} tan45=\frac{138ft}{x} \\ 1=\frac{138ft}{x} \\ x=138ft \end{gathered}$

So the distance from point A to B is=600ft - 138ft = 462ft