1=2?

I can prove 1 = 2

$\boxed{\text{Step1}}$ Lets say y = x
$\boxed{\text{Step2}}$ . Multiply by x xy = $x^2$
$\boxed{\text{Step3}}$ Subtract $y^2$ from each side xy - $y^2$ = $x^2$ - $y^2$
$\boxed{\text{Step4}}$ Factorize each side y(x-y) = (x+y)(x-y)
$\boxed{\text{Step5}}$ Divide both sides by (x-y) y = x+y
$\boxed{\text{Step6}}$ Since x = y y = y + y
$\boxed{\text{Step7}}$ And so... y = 2y
$\boxed{\text{Step8}}$ Divide both the sides by y $\boxed{\text{1 = 2}}$
Which step is wrong?