Question

19(у-9)=3(у+7);
4(х-9)=3(х-8);
3(2х-9)=5(х-4);
7(3-2х)=15(1-х);

Answer 1

19y-171=3y+21
19y-3y=171+21
16y=192
y=192:16
y=12

4x-36=3x-24
4x-3x=36-24
x=12

6x-27=5x-24
6x-5x=27-24
x=3

21-14x=15-15x
-14x+15x=15-21
x=-6

Answer 2

19y-171=3y+21
16y=192
y=12

4x-36=3x-24
x=12
и т. д.