X-百分之30X=91
问题描述:
X-百分之30X=91
答
X-30%X=91
70%X=91
X=91/70%=130
答
x-30%x=91
70%x=91-----------合并同类项(x看做100%x)
x=130-------------等式原理2
答
x-30%x=91
70%x=91
x=130