Algebra Lesson: Multiplication and Division Equations

Lesson Overview

• What Is Algebra?
• Important Symbols in Algebra
• Multiplication in Algebra
• Division in Algebra
• How to Use Reverse Operations
• Step-by-Step Practice
• Tips for Success in Algebra

Have you ever seen a math question with a blank or a letter like x or y and wondered what it means? That's algebra! Algebra helps us solve problems when we don't know all the numbers right away. Instead of guessing, we use rules to find the missing number.

In this lesson, you will learn how to solve algebra problems using multiplication and division. We will look at how to find missing numbers in easy steps.

What Is Algebra?

Algebra is a part of math that uses letters or blanks to show numbers we do not know yet. These letters are called variables. In most problems, we find out what the variable stands for.

Example:

• x + 5 = 12
  
  What number added to 5 gives 12?
  
• 12 - 5 = 7
• So, x = 7

Algebra is like solving a puzzle. You use numbers you know to find the number you don't know.

Important Symbols in Algebra

Here are some symbols used in algebra:

Multiplication in Algebra

Sometimes a number is missing in a multiplication sentence. To find the missing number, you do the opposite: divide.

Example:

• __ × 10 = 70
• 70 ÷ 10 = 7
• The missing number is 7

More Examples:

• 8 × __ = 32 → 32 ÷ 8 = 4
• __ × 6 = 42 → 42 ÷ 6 = 7
• 3 × __ = 27 → 27 ÷ 3 = 9
• 4 × __ = 24 → 24 ÷ 4 = 6
• __ × 3 = 9 → 9 ÷ 3 = 3
• 2 × __ = 18 → 18 ÷ 2 = 9
• __ × 7 = 49 → 49 ÷ 7 = 7
• __ × 8 = 64 → 64 ÷ 8 = 8

Take This Quiz-

Introduction to Algebra Test

Division in Algebra

Sometimes the missing number is part of a division sentence. To find it, you use multiplication.

Example:

• __ ÷ 10 = 4
• 4 × 10 = 40
• The missing number is 40

More Examples:

• 30 ÷ __ = 6 → 30 ÷ 6 = 5
• __ ÷ 3 = 7 → 3 × 7 = 21
• __ ÷ 2 = 4 → 2 × 4 = 8
• 33 ÷ __ = 3 → 33 ÷ 3 = 11

How to Use Reverse Operations

To solve algebra problems, use the opposite operation.

• If it is multiplication (×), use division (÷)
• If it is division (÷), use multiplication (×)

Examples:

• __ × 9 = 36 → 36 ÷ 9 = 4
• __ ÷ 2 = 4 → 2 × 4 = 8

This way, you can always find the missing number.

Step-by-Step Practice

Let's solve some problems step by step.

Problem 1: 8 × __ = 32

Step: 32 ÷ 8 = 4
Answer: 4

Problem 2: __ ÷ 3 = 7

Step: 3 × 7 = 21
Answer: 21

Problem 3: __ × 6 = 42

Step: 42 ÷ 6 = 7
Answer: 7

Problem 4: 33 ÷ __ = 3

Step: 33 ÷ 3 = 11
Answer: 11

Always check your answer by putting it back in the question.

Take This Quiz-

Grade 4 Algebra Quiz

Tips for Success in Algebra

• Know your multiplication tables
• Use the opposite operation to find the answer
• Always check your work
• Practice every day
• Don't be afraid to take your time