Question

Which is the longest side in the triangle $PQR$, right - angled at $P$?

Answer 1

In a triangle, the side which is opposite to largest angle is the longest side.

Now, In a right - angled triangle, largest angle is always ${90}^{\circ }$.

So, the side which is opposite to ${90}^{\circ }$ is longest side.

Since, the side opposite to right - angle is known as "Hypotenuse".

Hypotenuse of a triangle is the longest side of a triangle.

In $\Delta PQR$, if $\angle P={90}^{\circ }$ then $QR$ is the longest side.

Hence, $QR$ is the longest side.