|x+y-5|+(xy-6)²=0x+y-5=0,xy-6=0x+y=5xy=6x²+y²=(x+y)^2-2xy=25-2*6=13
由于绝对值|x+y-5|≥0与(xy-6)^2≥0要使它们的和等于0则应有x+y-5=0且xy-6=0所以由x+y-5=0,xy-6=0可解得x=2,y=3或x=3,y=2于是x^2+y^2=13。
由|x+y-5|+(xy-6)²=0可知x+y=5xy=6x²+y²=(x+y)²-2xy=9