Easy Algebra Step-by-Step: Master High-Frequency Concepts and Skills for Algebra Proficiency—FAST! (2012)

Chapter 10. Simplifying Polynomial Expressions

In this chapter, you apply your skills in multiplying polynomials to the process of simplifying polynomial expressions.

Identifying Polynomials

A polynomial expression is composed of polynomials only and can contain grouping symbols, multiplication, addition, subtraction, and raising to nonzero powers only.

No division by polynomials or raising polynomials to negative powers is allowed in a polynomial expression.

Problem Specify whether the expression is a polynomial expression.

b.

e.

Solution

Step 1. Check whether the expression meets the criteria for a polynomial expression.

is composed of polynomials and contains permissible components, so it is a polynomial expression.

b.

Step 1. Check whether the expression meets the criteria for a polynomial expression.

is not a polynomial expression because it contains division by 2x².

Step 1. Check whether the expression meets the criteria for a polynomial expression.

is composed of polynomials and contains permissible components, so it is a polynomial expression.

Step 1. Check whether the expression meets the criteria for a polynomial expression.

is not a polynomial expression because it is not composed of polynomials.

e.

Step 1. Check whether the expression meets the criteria for a polynomial expression.

is not a polynomial expression because it contains division by a polynomial.

Step 1. Check whether the expression meets the criteria for a polynomial expression.

is composed of polynomials and contains permissible components, so it is a polynomial expression.

Simplifying Polynomials

When you simplify polynomial expressions, you proceed in an orderly fashion so that you do not violate the order of operations for real numbers. After all, the variables in polynomials are simply stand-ins for real numbers, so it is important that what you do is consistent with the rules for working with real numbers.

Simplifying Polynomial Expressions

To simplify a polynomial expression:

1. Simplify within grouping symbols, if any. Start with the innermost grouping symbol and work outward.

2. Do powers, if indicated.

3. Do multiplication, if indicated.

4. Simplify the result.

Problem Simplify.

Solution

Step 1. Do multiplication:

Step 2. Simplify the result.

Step 3. Review the main steps.

Do multiplication before addition, if no parentheses indicate otherwise.

Step 1. Do multiplication:

Step 2. Simplify the result.

Step 3. Review the main steps.

Step 1. Do multiplication: –x(3y – 5x).

Step 2. Simplify the result.

Step 3. Review the main steps.

Step 1. Do the power: (x – 1)².

Step 2. Do multiplication: (2x – 1)(3x – 4).

Step 3. Simplify the results.

Step 4. Review the main steps.

Step 1. Simplify within the brackets. First, do multiplication: 5(x – 4).

Step 2. Simplify 3x + 5x – 20 within the brackets.

Step 3. Do multiplication: –4[8x – 20

Step 4. Simplify the result.

Step 5. Review the main steps.

Step 1. Do the power: (x + 1)².

The exponent applies only to

Step 2. Do multiplication:

Step 3. Review the main steps.

Exercise 10

Simplify.