# What is FOIL?

Mar 20, 2018

It's a rule.

#### Explanation:

It's a rule commonly used in factoring, meaning to start by multiplying the two first variables first, then outer, then inner, then last.
Ex:
If the things being multiplied is (x+1) by (x-2), you would multiply "x" and "x" first.
$x \cdot x = {x}^{2}$
$x \cdot - 2 = - 2 x$
$1 \cdot x = x$
$1 \cdot - 2 = - 2$
The final answer would be: ${x}^{2} - x - 2$