2x+10(28-x)=120解:去括号得:2x+280-10x=120移项得:2x-10x=120-280合并同类项得:-8x=-160系数化为1得:x=20。
解:2x+10(28-x)=1202x+280-10x =1208x=280-1208x=160x =20
2x+10(28-x) = 1202x + 280 - 10x = 1208x = 160x = 20