Question

решите: (3а+в)-(а-2в)
2(х+у)-3(х-у)-(у-х)

Answer 1

(3a+b) - (a-2b) = 3a+b - a +2b = 2a +3b.
2(x+y) - 3(x-y)-(y-x) = 2x +2y - 3x +3у - у +х = 3х -3х +4у = 4у.