4(100-15x)=70+25x
400-60x=70+25x
400-35x=70
35x=400-70
35x=7/66
2/3-8x=3-1/2x
2/3-15/2x=3
15/2x=2/3-3
15/2x=﹣7/3
x= - 14/45第一题。。。解二不是400-70=60x+25x