30/x=30/x-1+1.5怎么解
问题描述:
30/x=30/x-1+1.5怎么解
答
题目是30/x=30/(x-1)+1.5吧
30/x-30/(x-1)-1.5=0
两边同时乘于x(x-1)
30(x-1)-30x-1.5x(x-1)=0
-1.5x^2+1.5x-300=0
x^2-x+20=0
(x-5)(x+4)=0
x=5或x=-4