Look for the largest whole number you can factor out of 8 and 18.
This is 2.
Now look for the LARGEST power of x you can factor out. This is
the SMALLEST power that occurs, but x must appear in ALL terms.
This is
Now look for the LARGEST power of y you can factor out. This is
the SMALLEST power that occurs, but y must appear in ALL terms.
This is
So factor out
Now the expression in parentheses is the difference of two
perfect squares. is the same as and
is the same as so that expression in
parentheses factors as the sum of times difference of the bases
of those perfect squares, i.e., their square roots:
Edwin