已知(x-y):y=2:3,求(2x+5y)⼀(3x-2y)=?

2025-01-06 05:27:11
推荐回答(2个)
回答1:

∵(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

回答2:

(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