1 1 —x+0.4=—x-0.25 15 121 1—x+0.4=—x-0.2515 12

问题描述:

1 1 —x+0.4=—x-0.25 15 12
1 1
—x+0.4=—x-0.25
15 12

4x+24=5x-15
x=39