实数x,y满足√2x-3y-1+ |x-2y+2| =0
因为√2x-3y-1与 |x-2y+2| 都≥0
所以,2x-3y-1=0
x-2y+2=0
y=5,x=8
4y/(4x-5)
=20/(32-5)
=20/27
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后面你写的不明确,或者是：
4x-(4y/5)
=32-(20/5)
=32-4
=28