## Precalculus (6th Edition) Blitzer

$809$ m
The trigonometric ratios are as follows: $\sin \theta= \dfrac{opposite}{hypotenuse}$ ; $\cos \theta= \dfrac{Adjacent}{hypotenuse}$ and $\tan \theta= \dfrac{Opposite}{Adjacent}$ Our equation uses cosine: $\cos 72^{\circ}= \dfrac{250}{c}$ Our answer is: $c=\dfrac{250}{\cos 72^{\circ}}=809 m$