[tex]a)xy=2y\\xy-2y=0\\y(x-2)=0\\y=0 V x-2=0\\y=0 V x=2[/tex]
[tex]b) (x+5)(y-3)=0\\x+5=0 V y-3=0\\x=-5 V y=3[/tex]
[tex]c)x^{2} =y^{2} \\x=y V x=-y\\y=xV y=-x[/tex]
[tex]d)4x^{2} +4xy+y^{2} -0\\(2x+y)^{2} =0\\2x+y=0\\y=-2x[/tex]
[tex]e)(x+y)^{2} -4=0\\(x+y)^{2}=4\\x+y=2Vx+y=-2\\y=-x+2Vy=-x-2[/tex]
[tex]f)9x^{2} =(y+1)^{2} \\y+1=3xVy+1=-3x\\y=3x-1Vy=-3x-1[/tex]
