1/[(1/x)+(1/y)]=24,[1-(20/x)]/(y/1)=40

来源：学生作业帮编辑：作业帮分类：数学作业时间：2024/05/22 16:48:01

1/[(1/x)+(1/y)]=24,[1-(20/x)]/(y/1)=40
头大的用图
气死我了

1/x+1/y=1/24
所以1/x=1/24-1/y
(1-20/x)÷1/y=y(1-20/x)=40
所以y[1-20(1/24-1/y)]=40
y(1/6+20/y)=40
y/6+20=40
y/6=20
y=120
1/x=1/24-1/y=1/30
x=30
所以x=30,y=120

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