Suppose q and p are odd primes and p = q+4a for some integer a. From the properties of the Legendre symbol and the Law of Quadratic Reciprocity prove that the following two identities hold.
(p/q) = (a/q), and (a/p) = (a/q)
So i first did the LAW, such that if p=q=3 (mod4) then either (p/q) = -(q/p) or (p/q) = (q/p)
with that i did some mod stuff like, p = 4a(mod q) and 4a = p (mod q) this kind of implies that (p/q) = (a/q) right?