Objective

By the end of this lesson, you will be able to apply the PEMDAS rule to solve algebraic expressions and equations.

Materials and Prep

• Pencil and paper
• Calculator (optional)
• Prior knowledge of basic arithmetic operations and algebraic expressions

Activities

1. Warm-up: Start by reviewing the order of operations (PEMDAS) with the student. Ask them to solve simple arithmetic expressions using the correct order of operations. For example, 3 + 4 x 2 - 5.

2. Introduce algebraic expressions: Explain to the student that algebraic expressions involve variables and constants. Provide examples of algebraic expressions and ask the student to simplify them using the order of operations. For example, 2x + 3y - 4z.

3. Practice with parentheses: Give the student algebraic expressions with parentheses and ask them to simplify them. Emphasize the importance of performing operations within parentheses first. For example, (2 + 3) x (4 - 1).

4. Challenge with exponents: Introduce expressions with exponents and guide the student through simplifying them. Make sure they understand the rules for exponents, such as multiplying and dividing with the same base. For example, 2^3 x 2^2.

5. Apply PEMDAS to equations: Show the student algebraic equations and ask them to solve for the variable. Remind them to apply the order of operations correctly. For example, 3x + 5 = 17.

Eighth Grade Talking Points

• "PEMDAS stands for Parentheses, Exponents, Multiplication and Division (from left to right), and Addition and Subtraction (from left to right). It is a set of rules we follow to solve mathematical expressions."
• "Algebraic expressions involve variables (like x, y, z) and constants (numbers). We can simplify these expressions using PEMDAS."
• "When we see parentheses in an expression, we perform the operations inside the parentheses first."
• "Exponents represent repeated multiplication. For example, 2^3 means multiplying 2 by itself three times."
• "Equations are expressions with an equal sign (=). We use PEMDAS to solve equations and find the value of the variable."