Pascal's Triangle is probably the easiest way to expand binomials. It's much simpler to use than the Binomial Theorem, which provides a formula for expanding binomials. Pascal noticed
The formula for Pascal's Triangle comes from a relationship that you yourself might be able to see in the coefficients below.
The demonstration below illustrates the pattern. Pascal's Triangle presents a formula that allows you to create the coefficients of the terms in a binomial expansion.