Rational Expressions: Multiplying & Dividing

After reviewing the steps to find excluded values and to simplify rational expressions (from Friday), we looked at multiplying and dividing rational expressions.

To Multiply Rational Expressions:

1. Write each expression as a fraction.
2. Factor each expression. Remember, GCF first. Then try to factor a quadratic polynomial.
3. Cancel common factors either vertically or diagonally. But NOT horizontally.
4. Multiply the remaining expressions by multiplying "straight across". Numerator times numerator. Denominator times denominator.

Example:


To Divide Rational Expressions:

1. Write each expression as a fraction.
2. Change to a multiplication problem by flipping the second fraction over (reciprocal!). Many students know this step as "KFC" for Keep, Flip, Change.
3. (Now follow multiplication steps.) Factor each expression
4. Cancel common factors vertically or diagonally.
5. Multiply the remaining expressions straight across.

Example:

Homework: Page 167, #2 - 8 even, #10 - 17 all; Page 168, #2, 4, 8, 10, and 14

Extra Help: The IAA teachers are offering extra help for 30 minutes Tuesdays and Thursdays, before and after school. Students can attend any session, no matter who their teacher is.

Tuesday, 7:45 am, with Mr. Roth in P-123
Tuesday, 3:30 pm, with me, in room 4303
Thursday, 7:45 am, with Ms. Dufresne in room 5207
Thursday, 3:30 pm, with Mrs. Martina in room 5202

Also, if students need more practice with a lesson they can try Purple Math.com or the textbook website for additional tutorials & practice.

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