1)9 (х +6) =72
2)23 (х- 12)=552
3)15 (2х + 11) =285
4)7 (123-4х ) = 749

1)9х+54=729х=72-54 9х=18 х=22)23х-276=552 23х=828 х=36 3)30х+165=285 30х=120 х=4 4)861-28х=749 -28х=112 х=-4