Решите уравнение:
х + 2х = 21,42
2х + 5х = 42,7
12х - 3х = 41,4
7х - 4х = 0,96

1)х + 2х = 21,423х=21,42х=21,42:3х=7,142)2 х + 5х = 42,77х=42,7х=42,7:7х=6,13)12х - 3х = 41,49х=41,4х=4,64)7х - 4х = 0,963х=0,96х=0,96:3х=0,32