Adding and Subtracting Rational Expressions with Unlike Denominators

Objectives:

• Students will review adding/subtracting rational numbers.

• Students will learn how to find the LCD and rename rational numbers and expressions.

• Students will practice adding/subtracting rational expressions with unlike denominators.

Suggested Grades:

Seventh Grade - Eighth Grade - Ninth Grade - Tenth Grade - including special education students

Lesson Procedure:

Print the classroom lesson plan and worksheet questions (see below).

Lesson Excerpt:

I. Introduction

- "Today we are going to learn about adding and subtracting rational expressions that do not have common denominators. In the past, we have been adding and subtracting rational expressions with like denominators. When our rational expressions that had common denominators, we only had to add or subtract the numerators because the denominators were already alike. Now we are going to need to get a common denominator and then add or subtract the numerators."
- "But first, let's take a minute and review how to add/subtract rational numbers because some of this will apply once we begin working on rational expressions."
- "Here is an example."

Continued...