Download Warm up: p. 163 "Practice Quiz 1" OBJECTIVES: • find the Greatest

OBJECTIVES:
• find the Greatest Common Factor of two or more numbers
or monomials
• use the Distributive Property to factor algebraic expressions
Warm up: p. 163
Section 4­4
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"Practice Quiz 1"
Venn diagram ­­
20
12
The Venn diagram on the
right shows the prime factors of 12 and 20. The common prime
factors are in both circles.
2
3
2
5
a. Which numbers are in both circles?
b. Find the product of the numbers that are in both circles.
c. Is the product also a factor of 12 and 20?
Greatest Common Factor ­­
Example 2: Find the GCF of each set of numbers.
a. 30 and 24
b. 54, 36, 45
Example 1: Find the GCF of 12 and 20
Step 1: Write as prime factors
Step 2: Circle the ones that are the same
Step 3: Multiply the common primes from one row
12 = 2 2 3
20 = 2 2 5
GCF = 1
Example 3: There are 208 boys and 240 girls participating in a field day competition. Example 4: Find the GCF of the monomials.
16xy2 and 30xy
a. What is the greatest number of teams that can be formed
if each team has the same number of girls and the same
number of boys?
b. How many boys and girls will be on each team?
Example 5: Factor 2x + 6
Guided Practice:
Step 1: Find the GCF of the terms
Step 2: Write each term as a product of the GCF and other factors.
Step 3: Use the reverse of the Distributive Property.
1. Find the error. Christina and Jack both found the GCf of 2 32 11 and 23 5 11. Who is correct? Why? Christina
Jack
2 33 11
2 32 11
23 5 11
2 2 2 5 11
GCF = 11
GCF = 2 11
= 22
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Find the GCF of each set of numbers or monomials.
2. 6 and 8
3. 21, 45
4. 16, 56
5. 28, 42
Factor each expression.
10. 3n + 9
11. t2 + 4t
12. 15 + 20x
13. 4y ­ 16
6. 7, 30
7. 108, 144
8. 14n, 42 n2
9. 36a3b, 56ab2
14. In the parade, 36 members of the color guard are to march in front of 120 members of the marching band. Both groups are to have the same number of students in each row. Find the greatest number of students in each row.
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Do you have any Vocab questions?
OBJECTIVES:
HOMEWORK: p. 167 ­ 168
# 18 ­ 54 even, 59, 60
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