Warm Up # _____Write on a new page***

Add or subtract.

5.3 Adding and Subtracting Rational Expressions

Objective: Students will be able to add and subtract rational expressions.

Adding and Subtracting Rational Expressions with Like Denominators Directions: Add or subtract. Identify any x-values for

which the expression is undefined. Example 1:

Example 2

Your turn… Example 3:

Example 4:

Least Common MultipleLCM – the smallest number that is a multiple of two

other numbers. (Ex: the LCM of 3 and 5 is 15, because that is the smallest number that is a multiple of both 3 & 5.)

Finding the LCM:Step 1: Factor each polynomial completely and write any

repeated factors as powers.Step 2: List the different factors. Take the highest power of

any common factors.

Finding the LCMFind the LCM for each pair.

Example 5: 4x3y7 and 3x5y4

Example 6: x2 – 4 and x2 + 5x + 6

Adding Rational ExpressionsAdd. Identify any values that make the expression

undefined. Example 7:

Example 8

Example 9

Homework for tonightHomework # ____

Textbook pg. 332 # 17, 18, 20, 21, 22, 23, 25, 29