Use variables to represent numbers and write expressions when solving a real-world or mathematical problem; understand that a variable can represent an unknown number, or, depending on the purpose at hand, any number in a specified set.

Lesson Videos:

#### Understand how variables are used

In this lesson you will learn how a variable is used by examining real world scenarios.

#### Write algebraic expressions using addition and subtraction

In this lesson you will learn how to write addition and subtraction algebraic expressions by using a table.

#### Write algebraic expressions using multiplication and division

In this lesson you will learn how to write multiplication and division algebraic expressions by using a table.

#### Write multi-step algebraic expressions

In this lesson you will learn how to write multi-step algebraic expressions by examining a real world scenario.

#### Determine whether an algebraic expression matches a scenario

In this lesson you will learn how to determine whether an algebraic expression matches a scenario by analyzing a real world example.

#### Isolation Drills:

Constructing linear equations word problems

Using inequalities to describe real-world contexts

#### Interactive Practice:

- Solving Equations Using Inverse Operations – Explanation, examples and fifteen sample questions plus one standardized test practice question on this worksheet
- Algebraic Expressions – Explanation, examples, and several practice problems
- Beginning Algebra Tutorial 4: Introduction to Variable Expressions and Equations – Introduction, tutorial, lots of examples followed by practice problems
- Evaluate a Formula Using Substitution – Short video lesson
- Evaluate Expressions – Substitute values for variables in algebraic expressions and evaluate the expressions
- Evaluating an Expression with One Variable – Explanation, practice and a game
- Evaluating Expressions – Explanation, examples and a workout
- Evaluating Expressions with Two Variables – Explanation, practice and a game
- Evaluation: Evaluating Expressions, Polynomials, and Functions – Two-page lesson from Purple Math
- Expression Evaluation Calculator – Enter your expression and click on Evaluate.
- Expression Evaluation; Introduction to Expressions – First page of a multi page lesson with many examples and images
- Interactive Algebra Tiles – Use this to model an equation or to solve an equation
- Learning ratios and proportions through scale drawings – A text lesson plan
- Linear Equations in One Variable – Tutorial with examples, several video clips are available to help student understanding
- Math Word Problems – Eight question multiple choice quiz [Variation or Inverse Proportion]
- Patterns in Algebra – Find the relationship between two variables by using a table to find the pattern on this worksheet
- Solve Equations with Algebra – How to solve linear equations in one variable using algebra
- Solving One-Step Linear Equations – Four page lesson from Purple Math, includes a Mathway widget to practice
- Solving Problems Involving Direct Proportion – Some good practice problems are presented here, UK units used [close the subscription screen to get to the problems]
- Solving Proportion Problems – Four examples with detailed explanation
- Taming Word Problems – An Internet4Classsrooms WebQuest related to this standard
- Translating Word Problems – Lesson with links to practice types of word problems
- Translating Words Into Symbols – Translating words into symbols is equivalent to modeling a situation using an equation and variables
- Using Inverse Operations to Solve Equations: When Students Ask – Suggestions for ways to answer student questions regarding this standard
- Using Letters as Variables in Algebra – Part of the Making Math Meaningful series
- Variables and Constants in Algebra – From School for Champions
- What Variable Would You Use …? – An answer from Wiki Answers
- Why Do We Use Variables in Algebra? – From Ask Dr. Math
- Writing Algebraic Equations – Explanation, examples, and five practice exercises to work