Question

its asking for the approximate depth of the river. but I don't know how to determine that

Answer 1

From figure, trngles VWX and VYZ are similar.

So, the ratio of corresponding sides of triangles will be equal. Hence,

$\begin{gathered} \frac{VW}{VY}=\frac{WX}{YZ} \\ \frac{3}{62}=\frac{5}{d} \\ d=\frac{5\times62}{3} \\ =103.3\text{ m} \end{gathered}$

Therefore, the approximate depth of the river is d=103.3 m.