Show that if is a quadratic residue and then is a quadratic residue .

I am not sure where to go with this proof, I started with:

because is a quadratic residue.

Stumped right here.

Then I thought maybe using Legendre's symbols would be better.

because is a quadratic residue

So I have two starting points and no finish line in sight.

Thanks in advance for any help.

But not sure where to go to show that