0.6(x+7)-0.5(x-3)=6.8
0.6x+4.2-0.5x-(-1.5)=6.8
0.6x+4.2-0.5x+1.5=6.8
0.6x-0.5x=6.8-1.5-4.2
0.1x=1.1
x=11
Проверка:
0.6(11+7)-0.5(11-3)=6.8
0.6*18-0.5*8=6.8
10.8-4=6.8
6.8=6.8
0.6(x+7)-0.5(x-3)=6.8
0.6x+0.6*7-0.5x+0.5*3=6.8
0.6x+4.2-0.5x+1.5=6.8
0.1x=1.1
x=11
ответ: x=11.
