4(х+2)-7(2х-1)=30-9(3х-4) 8(7-4у)-19=7(4у+1)-5(8у-1) 3(2х+1)+7(6х-1)=23+5(12х-7) 17(3х+4)+13(5-4х)=11(7х-11)+20

4x+8-14x+7=30-27x+36

4x-14x+27x=30-8-7+36

17x=51

x=3

56-32y-19=28y+7-40y+5

-32y-28y+40y=-56+19+7+5

-20y=-25

20y=25

y=1.25

6x+3+42x-7=23+60x-35

6x+42x-60x=23-3+7-35

-12x=-8

12x=8

x=0.66

51x+68+65-52x=77x-121+20

51x-52x-77x=-121-68-65+20

-78x=-234

78x=234

x=3

4x + 2x - 14x +7 = 30- 27x -36 ; 

-12x-27x=-6-7

-39x=-13

x=3