Answer:
The proof is explained below
Step-by-step explanation:
Given right angled triangle and also the median we have to prove that the median to the hypotenuse of a right triangle is half the hypotenuse i.e 
In ΔORN, by Pythagoras theorem

In ΔORM, by Pythagoras theorem

Adding above two equations, we get

⇒ 
⇒ 
Since P is the mid-point i.e MP=PN

=
⇒ 
⇒ 
⇒ MN=2OP ⇒ 
Hence Proved.