а) (х-1) + (12-7.5х) = х - 1 + 12 - 7.5х = -6.5х + 11
б) 3(6-5х) + 17х - 10 = 18 - 15х + 17х - 10 = 2х + 8.
а) (х-1) + (12-7.5х) = х - 1 + 12 - 7.5х = -6.5х + 11
б) 3(6-5х) + 17х - 10 = 18 - 15х + 17х - 10 = 2х + 8.