①已知x^2+4y^2+6x-4y+10=0,求xy ②已知a^2-6a+b^2-6b+18=0,求a+b

问题描述:

①已知x^2+4y^2+6x-4y+10=0,求xy ②已知a^2-6a+b^2-6b+18=0,求a+b