The tops of two poles of height 40m and 25m are connected by a wire...

Let, $AB = 40$ and $CD = 25$ be the two poles.
$AC = l$ is the length of the wire.
$CE$ is the horizontal through $C$ and $∠ACE = \alpha$
$\dfrac{AE}{l} = sin \alpha ⇒ l = \dfrac{15}{sin \alpha} = \dfrac{30\sqrt{2}}{\left(\sqrt{3} - 1\right)} ⇒ sin \alpha = \dfrac{\sqrt{3} - 1}{2\sqrt{2}}$

Hence, $\sqrt{2}sin\alpha = 0 . 35$