3 birds were sitting on the fence. 6 more storks and 2 more birds came to join them. How many more storks than birds are sitting on the fence?
There are $x$ birds and $y$ storks sitting on the fence. 

$x+y=3$

$x+y+6+2=12$

$x+y=12-8=4$

$x=4-y$

$x-y=4-2y$

$y=4-x$

$y-x=4-2x$

$x=4-y$

$x-y=4-2y$

$y=4-x$

$y-x=4-2x$

$x=4-y$

$x-y=4-2y$

$y=4-x$

$y-x=4-2x$

$x=4-y$

$x-y=4-2y$

$y=4-x$

$y-x=4-2x$

$x=4-y$

$x-y=4-2y$

$y=4-x$

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