Simplifying the Sum or Difference of Two Polynomials

Oct 13, 2025 by wbrum.org 61 views

Introduction

In algebra, simplifying expressions is a crucial skill that helps us solve equations and inequalities. In this article, we will focus on simplifying two types of algebraic expressions: the sum or difference of two polynomials and the product of two binomials. We will use the given problem as a guide to demonstrate the steps involved in simplifying these expressions.

Simplifying the Sum or Difference of Two Polynomials

The first problem asks us to find the sum of two polynomials:

\left(-5x^3 + 2x + 1\right) + \left(3x^3 + 5x - 3\right)

To simplify this expression, we need to combine like terms. Like terms are terms that have the same variable raised to the same power.

Step 1: Identify Like Terms

The given expression has three terms in the first polynomial and three terms in the second polynomial. We need to identify the like terms:

The terms with the variable $x^3$ are $-5x^3$ and $3x^3$ .
The terms with the variable $x$ are $2x$ and $5x$ .
The constant terms are $1$ and $-3$ .

Step 2: Combine Like Terms

Now that we have identified the like terms, we can combine them:

\left(-5x^3 + 3x^3\right) + \left(2x + 5x\right) + \left(1 - 3\right)

Step 3: Simplify the Expression

We can simplify the expression by combining the like terms:

\left(-5x^3 + 3x^3\right) = -2x^3

\left(2x + 5x\right) = 7x

\left(1 - 3\right) = -2

So, the simplified expression is:

-2x^3 + 7x - 2

Simplifying the Product of Two Binomials

The second problem asks us to find the product of two binomials:

(x - 21)(x + 11)

To simplify this expression, we need to use the distributive property. The distributive property states that for any real numbers $a$ , $b$ , and $c$ :

a(b + c) = ab + ac

Step 1: Apply the Distributive Property

We can apply the distributive property to the given expression:

(x - 21)(x + 11) = x(x + 11) - 21(x + 11)

Step 2: Simplify the Expression

We can simplify the expression by multiplying the terms:

x(x + 11) = x^2 + 11x

-21(x + 11) = -21x - 231

So, the simplified expression is:

x^2 + 11x - 21x - 231

Step 3: Combine Like Terms

We can combine the like terms:

x^2 + 11x - 21x - 231 = x^2 - 10x - 231

Conclusion

In this article, we have demonstrated how to simplify two types of algebraic expressions: the sum or difference of two polynomials and the product of two binomials. We have used the given problem as a guide to show the steps involved in simplifying these expressions. By following these steps, we can simplify complex algebraic expressions and solve equations and inequalities.

Key Takeaways

To simplify the sum or difference of two polynomials, we need to combine like terms.
To simplify the product of two binomials, we need to use the distributive property.
We can simplify complex algebraic expressions by breaking them down into smaller parts and combining like terms.

Practice Problems

Simplify the expression: $$\left(2x^2 + 3x - 1\right) + \left(x^2 - 2x + 4\right)$$
Simplify the expression: $$(x + 2)(x - 3)$$

Answer Key

$3x^2 + x + 3$
$x^2 - x - 6$$<br/>$

Introduction

In our previous article, we demonstrated how to simplify two types of algebraic expressions: the sum or difference of two polynomials and the product of two binomials. In this article, we will provide a Q&A guide to help you understand the concepts and techniques involved in simplifying algebraic expressions.

Q: What is the difference between a polynomial and an algebraic expression?

A: A polynomial is an algebraic expression that consists of variables and coefficients combined using only addition, subtraction, and multiplication. An algebraic expression, on the other hand, can include variables, coefficients, and constants combined using various operations, including addition, subtraction, multiplication, and division.

Q: How do I simplify a polynomial expression?

A: To simplify a polynomial expression, you need to combine like terms. Like terms are terms that have the same variable raised to the same power. You can combine like terms by adding or subtracting their coefficients.

Q: What is the distributive property, and how do I use it to simplify expressions?

A: The distributive property is a mathematical concept that states that for any real numbers $a$ , $b$ , and $c$ :

a(b + c) = ab + ac

You can use the distributive property to simplify expressions by multiplying each term inside the parentheses by the term outside the parentheses.

Q: How do I simplify the product of two binomials?

A: To simplify the product of two binomials, you need to use the distributive property. You can apply the distributive property by multiplying each term in the first binomial by each term in the second binomial.

Q: What are some common mistakes to avoid when simplifying algebraic expressions?

A: Some common mistakes to avoid when simplifying algebraic expressions include:

Not combining like terms
Not using the distributive property when multiplying binomials
Not simplifying expressions fully

Q: How do I check my work when simplifying algebraic expressions?

A: To check your work when simplifying algebraic expressions, you can:

Plug in values for the variables to see if the expression simplifies correctly
Use a calculator to evaluate the expression
Check your work by simplifying the expression in a different way

Q: What are some real-world applications of simplifying algebraic expressions?

A: Simplifying algebraic expressions has many real-world applications, including:

Solving equations and inequalities
Modeling real-world situations using mathematical equations
Optimizing systems and processes

Conclusion

In this article, we have provided a Q&A guide to help you understand the concepts and techniques involved in simplifying algebraic expressions. By following these tips and techniques, you can simplify complex algebraic expressions and solve equations and inequalities.

Key Takeaways

To simplify a polynomial expression, you need to combine like terms.
To simplify the product of two binomials, you need to use the distributive property.
You can check your work by plugging in values for the variables or using a calculator.

Practice Problems

Simplify the expression: $$\left(3x^2 + 2x - 1\right) + \left(x^2 - 3x + 2\right)$$
Simplify the expression: $$(x + 1)(x - 2)$$

Answer Key

$4x^2 - x + 1$
$x^2 - x - 2$