# 18.2 Multiplying Polynomial Expressions

Polynomial expressions are mathematical expressions that contain terms with variables and constants. These expressions can be single terms, binomials, trinomials, and more. In this lesson, we will learn how to multiply polynomial expressions of different degrees. Understanding how to multiply polynomials is essential for many algebraic concepts.

## The FOIL Method

The most common method for multiplying polynomials is the FOIL method. The acronym FOIL stands for First, Outer, Inner, Last. It is a step-by-step process for multiplying two binomials (two polynomials of degree two). When multiplying two binomials, each term from the first binomial is multiplied by each term of the second binomial. This will create a four-term polynomial.

## Multiplying Trinomials

When multiplying trinomials, it is important to remember the distributive property. This states that for any two expressions, a(b+c) = ab + ac. This means that the first term of the trinomial (a) will be multiplied by each term of the second polynomial. The second term of the trinomial (b) will also be multiplied by each term of the second polynomial. The same goes for the third term of the trinomial (c). This will create a six-term polynomial.

## Multiplying Polynomials of Different Degrees

When multiplying polynomials of different degrees, it is important to remember that the degree of the resulting polynomial will be the sum of the degrees of the two polynomials being multiplied. For example, if you are multiplying a binomial (degree 2) and a trinomial (degree 3), the resulting polynomial will have a degree of 5. Each term of the higher degree polynomial will be multiplied by each term of the lower degree polynomial.

## 

Multiplying polynomial expressions is an important skill to understand in algebra. The FOIL method and the distributive property are essential for multiplying binomials and trinomials, respectively. It is also important to remember that the degree of the resulting polynomial will be the sum of the degrees of the two polynomials being multiplied. With practice and a little bit of practice, you can master the art of multiplying polynomial expressions.