a) [tex]a^2b^2c^2 - abc - a^2b^2c^2 - ab^2c + a^2bc^2 - a^2bc + ab^2c = -abc[/tex]
b) [tex]14ax - 8ay + 5ay - 3ax - 16ax + 4xy - 7 = -5ax - 3ay + 4xy -7[/tex]
