Question

|2x+y-3|+4x^2-4xy+y^2=0

Answer 1

$|2x+y-3|=sqrt{(2x+y-3)^2}\\ 4x^2-4xy+y^2=(2x-y)^2\\ sqrt{(2x+y-3)^2}+(2x-y)^2=0\\ 2x+y=3\ 2x=y\\ 4x=3\ x=frac{3}{4}\ y=frac{3}{2}$