解方程:(1200/x-2)-(1200/x)=30

问题描述:

解方程:(1200/x-2)-(1200/x)=30

方程两边同乘(x-2)x
得1200x-1200(x-2)=30*(x-2)x
1200x-1200x+2400=30x²-60x
30x²-60x-2400=0
x²-2x-80=0
(x-10)(x+8)=0
x=10或x=-8