Решите по алгебре номер4.39.

3х-6=х+4 3х-х=6+4 2х=10 х=10:2 х=5

1) 4(х+3)+5(х-3) = 105    4х + 12 + 5х - 15 = 105 9х - 3 = 105 9х = 105+3 9х = 108 х = 108:9 х = 12 2) 3(х+20) - 4х = 10 3х + 60 - 4х = 10 - х + 60 = 10 - х = 10 - 60 - х = - 50 х = 50 3) 2х + 3(х+10) = 380 2х + 3х +30 = 380 5х + 30 = 380 5х = 380 - 30 5х = 350 х = 350 : 5 х = 70 г) 5(х+2) - 6(х-2) = 5 5х + 10 -6х +12 = 5 -х + 22 = 5 -х = 5 - 22 - х = - 17 х = 17