问题 填空题
m、n满足|m+2|+
n-4
=0,分解因式:(x2+y2)-(mxy+n)=______.
答案

∵|m+2|+

n-4
=0,

∴m+2=0,n-4=0,

解得m=-2,n=4,

∴(x2+y2)-(mxy+n),

=(x2+y2)-(-2xy+4),

=x2+y2+2xy-4,

=(x+y)2-4,

=(x+y+2)(x+y-2).

判断题
单项选择题