(x²－4y²)/(x²+y²+2xy)÷(2y+x)/(x²+xy )=[(x+2y)(x-2y)]/[(x+y)^2]÷(2y+x)/x(x+y)=[x(x+2y)(x-2y)(x+y)]/(x+y)^2(2y+x)=[x(x-2y)]/(x+y)