(5p2-3) +(2p2 -3p3)
(4+2n3) + (5n3+2)
(4n-3n3) (3n3+4n)
(-4k4+14+3k2) + (-3k4 -14k2 -8)
(3-6n5-8n4) - (-6n4 -3n-8n5)
(-x4 +13x5+6x3) +(6x3+5x5+7x4)
(9r3+5r2+11r) +(-2r3 +9r-8r2)
(7-13x3-11x) - (2x3 +8-4x5)
(8b3-6+4b4) -(b2-7b3-3)
(8k+k2-6) -(-10k+7-2k2)