Jika x=2p-4q dan y=-4p+2q, maka nilai 2x²-3xy+y²/x²-y²

2(2p-4q)^2 -3(2p-4q)(-4p+2q) + (-4+2q)^2 : (2p-4q)^2 -(-4+2q)
=8p^2 – 32pq + 32q^2 – 24q^2 + 60pq-24q^2 +16-16q-4q^2 : 4p^2-16pq+16q^2+4-2q