∵│x-a│+(y+b)^2=0
两非负项和为0,则两项均为0
∴x-a=0,y+b=0
∴x=a,y=-b
（a^2+ay-bx+b^2)／(x+y)÷[(a^2+ax+by-b^2)／(a+b)]
=(a²-ab-ab+b²)/(a-b)÷[(a²+a²-b²-b²)/(a+b)]
=(a-b)²/(a-b) ×(a+b)/[2(a²-b²)]
=(a-b)×(a+b)/[2(a+b)(a-b)]
=1/2
【中学生数理化】团队为您答题,