Algebraic Expressions

Simplify, evaluate, and manipulate algebraic expressions with variables and operations.

7th Grade

Algebra

~45 min

🎮 Interactive Activity: Expression Evaluator

Evaluate algebraic expressions by substituting values!

If x = 4, evaluate:

3x + 5

🎮 Interactive Activity: Expression Simplifier

Simplify expressions by combining like terms!

5x + 3x + 2

1. Understanding Algebraic Expressions

What is an Algebraic Expression?

An algebraic expression is a combination of numbers, variables, and operations. It doesn't have an equals sign.

Example: Parts of an Expression

Consider: 3x + 5

• 3x is a term (coefficient: 3, variable: x)

• 5 is a constant term

• + is the operation

Key Terms:

• Variable: A letter representing an unknown value (x, y, a, b)
• Coefficient: The number multiplying a variable (in 5x, 5 is the coefficient)
• Constant: A number without a variable (in 3x + 7, 7 is the constant)
• Term: A number, variable, or product of numbers and variables

2. Simplifying Expressions

3. Evaluating Expressions

4. Distributive Property

5. Problem-Solving Strategies

6. Common Errors & Tips

Frequently Asked Questions

Practice Time!

Practice Quiz

Questions

Correct

Score

Simplify: 7x + 4x - 2x

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Simplify: 3(2x + 5) - 4x

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Evaluate 4a - 3b when a=6, b=2

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Factor: 8x + 16

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Simplify: 5x² + 3x - 2x² + 4x

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Expand: -2(x - 3)

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Write expression: 'Twice a number decreased by 5'

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What is the coefficient in -7y?

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Simplify: 2x + 3y - x + 5y

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Evaluate x² + 2x - 1 when x = 3

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