已知(x-y):y=2:3,求(2x+5y)/(3x-2y)=?

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已知(x-y):y=2:3,求(2x+5y)/(3x-2y)=?已知(x-y):y=2:3,求(2x+5y)/(3x-2y)=?已知(x-y):y=2:3,求(2x+5y)/(3x-2y)=?∵(x-

已知(x-y):y=2:3,求(2x+5y)/(3x-2y)=?
已知(x-y):y=2:3,求(2x+5y)/(3x-2y)=?

已知(x-y):y=2:3,求(2x+5y)/(3x-2y)=?
∵(x-y):y=2:3,
∴2y=3(x-y)
2y=3x-3y
2y+3y=3x
5y=3x
y=(3/5)x
∴2x+5y=5x,3x-2y=(9/5)x
∴(2x+5y)/(3x-2y)
=(5x)/[(9/5)x]
=25/9

(x-y):y=2:3
3(x-y)=2y
3x-3y=2y
3x=5y
x/y=5/3
(2x+5y)/(3x-2y)
=(2x+3x)/(5y-2y)
=5x/3y
=(5/3)*(5/3)
=5/3x5/3
=25/9