设A=2x^2-3xy+y^2-x+2y,B=4x^2-6xy+2y^2-3x-y 若/x-2a/+(y+3)^2=0且

来源：学生作业帮编辑：神马作文网作业帮分类：数学作业时间：2024/10/04 20:25:16

设A=2x^2-3xy+y^2-x+2y,B=4x^2-6xy+2y^2-3x-y 若/x-2a/+(y+3)^2=0且B-2A=a,求A的值?

|x+2a|+(y+3)^2=0
x=-2a,y=-3
B-2A=a
a=4x^2-6xy+2y^2-3x-y-2(2x^2-3xy+y^2-x+2y)
=4x^2-6xy+2y^2-3x-y-4x^2+6xy-2y^2+2x-4y
=-x-5y
|x-2a|
=|x-2(-x-5y)|
=|x+2x+10y|
=|3x+10y|
=|3x-30|
=0
解得x=10
A=2x^2-3xy+y^2-x+2y
=(x-y)(2x-y)-x+2y
=13×23-10-6
=283

设A=2x-3xy+y+x-3y,B=4x-6xy+2y+4x-y,若|x-3a|+（y+3）=0,且B-2A=a.求A 设A=2x²-3xy+y²-x+2y,B=4x²-6xy+2y²-3x-y,若x 设A=2x²-3xy+y²-x+2y,B=4x²-6xy+2y²+3x-y.若x 设A=2x*-3xy+y*-x+2y,B=4x*-6xy+2y*-3x-y,若|x-2a|+(y+3)*=0,且B-2A 设A=2x方-3xy+y方-x+2y,B=4x方-6xy+2y方+3x-y.若|x-2a|+（y+3）的平方=0,且B- 设A=2X²-3xy+y²-x+2y,B=4x²-6xy+2y²-3x-y,若| 设A=2x²-3xy+y²-x+2y,B=4x²-6xy+2y²+3x-y 若| 设A=2x²-3xy+y²-x+2y,B=4x²-6xy+2y²-3x-y,若│ 设A=2x²-3xy+y²-x+2y,B=4x²-6xy+2y²-3x-y,若| 1.设A=2x²-3xy+y²-x+2y,B=4x²-6xy+2y²-3x-y, 设A=2x²-3xy+y²-x+2y ,B=4x²-6xy+2y²+3x-y . 1.设A=2x²-3xy+y²+x-3y,B=4x²-6xy+2y²+4x-y,