设A=2X²-3xy+y²-x+2y,B=4x²-6xy+2y²-3x-y,若|x-2a|+(y+3)²=0,且-2A+B=a,求A

设A=2X²-3xy+y²-x+2y,B=4x²-6xy+2y²-3x-y,若|x-2a|+(y+3)²=0,且-2A+B=a,求A
设A=2X²-3xy+y²-x+2y,B=4x²-6xy+2y²-3x-y,若|x-2a|+(y+3)²=0,且-2A+B=a,求A

设A=2X²-3xy+y²-x+2y,B=4x²-6xy+2y²-3x-y,若|x-2a|+(y+3)²=0,且-2A+B=a,求A
由|x-2a|+(y+3)²=0可得x=2a,y=-3
带入A,B可得A=8a²+16a+3,B=16a²+30a+21
带入-2A+B=a得a=5,A=283