Put the a² over 11 so that everything on top
and bottom will be a fraction. I used 11 instead
of just 1 because it "stacks up" better using the forum's
notation system. You can just use 1 where I have 11.
Look at all the denominators on the top and the bottom.
Their LCD is z³. so multiply by , written as
In the upper left term you can cancel the z³'s,
The upper right term becomes just -z³a².
In the lower left term, subtract the exponents
of the z's and get simply zx.
In the lower right term you can cancel the z³'s,
So you end up with:
Now if you like you can factor out "a" on top:
but that step isn't necessary.