Foil stands for

if you had (a+b)(c+d) you would get this by foiling:

Ac+bc+ad+bd

a and c are the first nubers in eac h parenthisese,

b and c are the two numbers in the center

a and d are the two numers on the outside

b and d are last numbers in each parenthisese.

The samne goes for equations for more parenthisese. Hope this helps, and let me know if you need anything else!

**f**irst**I**nner**o**uter**l**astif you had (a+b)(c+d) you would get this by foiling:

Ac+bc+ad+bd

a and c are the first nubers in eac h parenthisese,

b and c are the two numbers in the center

a and d are the two numers on the outside

b and d are last numbers in each parenthisese.

The samne goes for equations for more parenthisese. Hope this helps, and let me know if you need anything else!