Question

A boat in a circular Lake lies at the centre about 10m away from the bridge lying in 40m distance across the circular lake. How much distance will boat have to travel to reach to the extreme point of left side of bridge?

Answer 1

Let O be the boat which is at the centre of the circular lake and let AB be the bridge.
Distance OM is 10 m.

$$\begin{gathered} \mathrm{Then}\mathrm{in}\mathrm{right}△\mathrm{AMO}, \\ \mathrm{AO}=\sqrt{{\mathrm{AM}}^2+{\mathrm{OM}}^2} \\ =\sqrt{{20}^2+{10}^2} \\ =10\sqrt{5} \\ =22.36\mathrm{m} \end{gathered}$$

Therefore, the boat has to travel 22.36 m to reach the extreme point on the left side of the bridge.