Упражнение 1 1) 8х + 4(5 – 3х) = 7 – 12х;
2) 15 – 5(8x + 6) = 3х – 28
3) 12x + 5(8 – 3x) = 9x + 6

1)8х+20-12х=7-12х
8х-12х+12х=7-20
8х=-13
х=-1,625
2)15-40х-30=3х-28
-43х=-13
х=13/43
3)12х+40-15х=9х+6
-12х=-34
х=34/12
4)23-12х-32=1-17х
5х=10
х=2