hasil ( P + Q + R )²

(P+Q+R)(P+Q+R)
=P^2 + PQ +PR +PQ +Q^2 +QR +PR +QR +R
P ^2+ 2PQ + 2PR + Q ^2+ 2QR +R^2

= 5a + 2b + 5 + 2a + 4b - 8 + -3a + 5b - 2 × 2
= 5a + 2a - 3a - 2b + 4b + 5b + 5 - 8 - 2 × 2
= 4a + 7b + 5 × 2
Maaf klo salah ^-^