Lesson objective: Compare arithmetic and algebraic approaches to solving problems.

This lesson helps to build procedural skill with algebraic and arithmetic problem solving. Comparison of the two approaches is used here because it encourages students to make connections between arithmetic and algebra. This work develops students' understanding that arithmetic and algebraic approaches are related.

Students engage in Mathematical Practice 7 (Look for and make use of structure) as they compare the two approaches and identify the same operations that are used in both.

**Key vocabulary:**

- algebraic approach
- arithmetic approach
- equation
- expression