In this Grade 7 enVision Mathematics lesson from Chapter 4, students learn how to add algebraic expressions by identifying and combining like terms using the Commutative and Associative Properties. The lesson covers adding expressions with one or more variables, including those with rational number coefficients such as decimals and fractions. Students apply these skills to real-world contexts like calculating total costs and profits represented by multi-term expressions.
Section 1
Concept: Adding Linear Expressions
To add linear expressions, we remove parentheses and combine like terms.
Like terms have the same variable with the same exponent.
For linear expressions, we combine constant terms together and variable terms with the same variable together.
To add like terms, we add their numerical coefficients.
Section 2
Adding Expressions with Multiple Variables
To add expressions with multiple variables, combine like terms by adding their coefficients. A variable without a written coefficient has an implicit coefficient of 1.
Section 3
Common Error: Keep the Variable Part the Same
When adding like terms, add their coefficients. The variable part of the term does not change.
Correct:
Expand to review the lesson summary and core properties.
Section 1
Concept: Adding Linear Expressions
To add linear expressions, we remove parentheses and combine like terms.
Like terms have the same variable with the same exponent.
For linear expressions, we combine constant terms together and variable terms with the same variable together.
To add like terms, we add their numerical coefficients.
Section 2
Adding Expressions with Multiple Variables
To add expressions with multiple variables, combine like terms by adding their coefficients. A variable without a written coefficient has an implicit coefficient of 1.
Section 3
Common Error: Keep the Variable Part the Same
When adding like terms, add their coefficients. The variable part of the term does not change.
Correct: