1-（x-y)/(x-2y)/(x^2-y^2)/(x^2-4xy+4y^2)实数x,y满足|2x-y+1|+2根号下3x-2y+4=0化简求值

∵实数x,y满足|2x-y+1|+2根号下3x-2y+4=0
∴|2x-y+1|=0且2根号下3x-2y+4=0
∴
{2x-y+1=0
{3x-2y+4=0
∴x=2,y=5
故
1-（x-y)/(x-2y)/(x^2-y^2)/(x^2-4xy+4y^2)
=1-（-3）/(-8)/(-10)/64
=-7/5要先化简再带入求值