亲,回复如下,请参考。
x-(1/4-1/5)=4/5
x-1/4 + 1/5=4/5
x-1/4 =4/5-1/5
x-1/4 =3/5
x=3/5+ 1/4
x=12/20+ 5/20
x=17/20
解:x=4/5+1/4-1/5x=3/5+1/4x=12/20+5/20x=17/20
x-(1/4-1/5)=4/5x-1/20=4/5x=4/5+1/20x=17/20
x-(1/4-1/5)=4/5x-1/20=4/5x=4/5+1/20x=7/20