Exercise 4.5.4 solution
Let \(b\) represent the width of the river. Then \(\dfrac{100}{b}=\tan31^\circ\). Thus, \(b=\dfrac{100}{\tan31^\circ}\approx166.4\) ft.
Let \(b\) represent the width of the river. Then \(\dfrac{100}{b}=\tan31^\circ\). Thus, \(b=\dfrac{100}{\tan31^\circ}\approx166.4\) ft.