Addition & Subtraction
| Site: | Clare-Gladwin RESD |
| Course: | Michigan Algebra II KHauck |
| Book: | Addition & Subtraction |
| Printed by: | Guest user |
| Date: | Saturday, November 23, 2024, 12:07 PM |
Description
Adding & Subtracting Rational Expressions
Review
Adding and subtracting fractions is a familiar process. The key is finding the Least Common Denominator (LCD) which is the smallest whole number that is divisible by each value in the denominator. In order to find the LCD, find the Least Common Multiple (LCM) of the values in the denominator(s). To review how to find the LCM select the following link.
Fractions
Once the LCD is found, write equivalent fractions using the LCD as the denominator. Finally, add the fractions by adding the numerators and writing the sum over the LCD.
Example Add and simplify.
Step 1. Find the Least Common Denominator.
The LCD of 2 and 3 is 6.
Step 2. Rewrite the fractions with the LCD.
*Remember: 
and multiplying by 1 does not change the value of an expression.
Step 3. Add the fractions.
Step 4.Simplify the fraction, if necessary.
LCM of Rational Expressions
Finding the LCM of fractions is essential to adding and subtracting rational expressions. To review how to find the LCM of polynomials select the following link:
Video Lesson: Adding
The review of adding and subtracting fractions will help when adding or subtracting rational expressions. To learn how to add rational expressions select the following link:
Video Lesson: Subtracting
To learn how to subtract rational expressions select the following link:
Subtracting Rational Expressions
Guided Practice
To solidify your understanding of adding and subtracting rational expressions, visit the following link to Holt, Rinehart and Winston Homework Help Online. It provides examples, video tutorials and interactive practice with answers available. The Practice and Problem Solving section has two parts. The first part offers practice with a complete video explanation for the type of problem with just a click of the video icon. The second part offers practice with the solution for each problem only a click of the light bulb away.
Self Test
To see how well you understand how to manipulate rational expressions, select the link below:
Practice
Adding and Subtracting Rational Expressions
*Note: If Google Docs displays “Sorry, we were unable to retrieve the document for viewing.†refresh your browser
Answer Key
Adding and Subtracting Rational Expressions Answer Key
Sources
Sources used in this book:Embracing Mathematics, Assessment & Technology in High Schools; a Michigan Mathematics & Science Partnership Grant Project
Holt, Rinehart & Winston, "Rational & Radical Expressions." http://my.hrw.com/math06_07/nsmedia/homework_help/alg2/alg2_ch08_03_homeworkhelp.html (accessed 6/16/2010).
Kenny Felder, "Rational Expression Concepts -- Adding and Subtracting Rational Expressions," Connexions, November 15, 2008, http://cnx.org/content/m18303/1.1/.
Pearson Prentice Hall, "Rational Expressions and Equations." 2010.http://www.phschool.com/webcodes10/index.cfm?fuseaction=home.gotoWebCode&wcprefix=aja&wcsuffix=0600 (accessed 6/16/2010).