Question

Using the data in the figure, calculate the width x of the river.(word upė means river)

Answer 1

Given:

is given.

Required:

We have to find the value of x

Explanation:

Here in figure, triangle ADE and triangle ABC are similar under AA similarity

$\begin{gathered} \angle D=\angle B \\ \angle E=\angle C \end{gathered}$

So by this we also write this

$\begin{gathered} \frac{AD}{AB}=\frac{ED}{CB} \\ \end{gathered}$

Now put the values

$\begin{gathered} \frac{2}{5}=\frac{4}{x} \\ \Leftrightarrow\frac{1}{5}=\frac{2}{x} \\ \Leftrightarrow x=10m \end{gathered}$

Final answer:

The value of x is 10m