5X +4X + 19X = 63 2 + 180 : ( 5x - 4x + x - 12) = 22 ЭТО УРАВНЕНИЯ!
5х+4х+19х=63 28х=63 Х=2,25 180:(5х-4х+х-12)=22-2 180:(5х-4х+х-12)=20 5х-4х+х-12=180:20 5х-4х+х-12=9 5х-4х+х=9+12 5х-4х+х=21 2х=21 Х=10,5