UC知道已知：A=3x二次方-6xy+9y二次方+2x-y B=x二次方-2xy+3y二次方-x+y,
来源：百度知道 编辑：UC知道 时间：2024/07/07 16:14:56
|x-a|+(y+3)二次方=0
x=a,y=-3
A=3x二次方-6xy+9y二次方+2x-y
=3a^2+18a+81+2a+3
=3a^2+20a+84
B=x二次方-2xy+3y二次方-x+y,
=a^2+6a+27-a-3
=a^2+5a+24
A-3B=(3a^2+20a+84)-3(a^2+5a+24)=5a+12=2a
3a=-12
a=-4
A+B=(3a^2+20a+84)+(a^2+5a+24)
=4a^2+25a+104
=64-100+104
=68
cocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hotmail.comcocoli_1994@hot