解方程:x/v-x/(y+8)=27/60,x/(y-4)-x/y=18/60_数学解答

解方程:x/v-x/(y+8)=27/60,x/(y-4)-x/y=18/60

人气：403 ℃　时间：2020-03-29 21:26:39

解答

先通分
x(y+8)-xy=27/60y(y+8)
xy-x(y-4)=18/60y(y-4)
8x=27/60y(y+8) (1)
4x=18/60y(y-4) (2)
(1)-(2)*2
y=40 x=108