1. 5-Minute Check on Chapter 2
Transparency 3-1
5-Minute Check on Chapter 2
Evaluate 42 - |x - 7| if x = -3
Find 4.1  (-0.5)
Simplify each expression
3. 8(-2c + 5) + 9c (36d – 18) / (-9)
A bag of lollipops has 10 red, 15 green, and 15 yellow lollipops. If one is chosen at random, what is the probability that it is not green?
Which of the following is a true statement
Standardized Test Practice: A
8/4 < 4/8 B
-4/8 < -8/4 C
-4/8 > -8/4 D
-4/8 > 4/8
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2. Multiplying Rational Expressions
Lesson 12-3
Multiplying Rational Expressions

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Transparency 3

4. Transparency 3a

5. Objectives Multiply rational expressions
Use dimensional analysis with multiplication

6. Vocabulary
None new

7. Key Concept
xxxxx

8. Example 1a
Find
Method 1: Divide by the greatest common factor after multiplying.
Multiply the numerators.
Multiply the denominators.
The GCF is 98xyz.
Simplify.

9. Example 1a cont Method 2 Divide the common factors before multiplying.
Divide by common factors and z. 1 x 6
z 2
y 3
Multiply.
Answer:

10. Example 1b Find Divide by common factors and r. Multiply. Answer: d 2
q 2
r 3
Multiply.
Answer:

11. Example 2a Find Factor the numerator. The GCF is Simplify. Answer: x 21
x 2
Simplify.
Answer:

12. Example 2b
Find
Factor.
The GCF is 1
Multiply.
Simplify.
Answer:

13. Example 3
Space The velocity that a spacecraft must have in order to escape Earth’s gravitational pull is called the escape velocity. The escape velocity for a spacecraft leaving Earth is about 40,320 kilometers per hour. What is this speed in meters per second?

14. Example 3 cont 1120 10 1 Simplify. Multiply.
Answer: The escape velocity is 11,200 meters per second.

15. Summary & Homework Summary: Homework:
Finding common factors to simplify numbers
Multiplying rational expressions is similar to multiplying rational numbers
Homework: pg