0,8х – 3,6 = 5,4 – 1,2х
0.8x-3.6=5.4-1.2x 0.8x+1.2x=5.4+3.6 2x=9 /÷2 x=4.5
0.8×+1.2×=3.6+5.4 2×=9 ×=9:2 ×=4.5 Проверка 4.5×0.8-3.6=5.4-1.2×4.5 3.6-3.6=5.4-5.4 0=0