Question

已知A=2x²+4xy-2x-3，B=-x²+xy+2，且3A+6B的值与x无关，你能求出y的值吗？

步骤完整

Answer 1

3A+6B=6x²+12xy-6x-9-6x²+6xy+12=18xy-6x+3=(18y-6)x+3
∵3A+6B的值与x无关
∴18y-6=0
∴y=1/3

Answer 2

3A+6B=6x^2+12xy-6x-9-6x^2+6xy+12=18xy-6x+3=6x(3y-1)+3
由于与x无关
所以3y-1=0
y=1/3