1) 3(х-7) + 5х = 3х - 21 + 5х = 8х - 21.
2) 5(4 - 3х) + 8х = 20 - 15х + 8х = 20 - 7х.
3) (у - 4) * 2 + 10у = 2у - 8 + 10у = 12у - 8.
4) (2у + 5) * 4 - 11у = 8у + 20 - 11у = -3у +20
5) 4х + 2(0,5х + 3) = 4х + х + 3 = 5х +3
6) 6х + 3(х - 7) = 6х + 3х - 21 = 9х - 21.