Multiply two binomials that have the same terms but different signs. One way is to FOIL it and then combine like terms. Another, shorter way to do it is to use a formula. There's a formula for the product of a sum and a difference. Using...

There is a shortcut formula for finding the product of a sum and a difference. Use the formula rather than FOILing out the monomials. Fewer steps mean fewer headaches in math.