Question

已知实数x,y满足2x的平方+6xy+9y的平方-2x+1=0,试求x,y的值

Answer 1

2x^2+6xy+9y^2—2x+1=0

x^2+6xy+9y^2+[x^2-2x+1]=0

[x+3y]^2+[x-1]^2=0

x+3y=0

x-1=0

x=1

y=-1/3

xy=-1/3