Prime Factorization

1. 4.3 Prime Factors
October 17, 2013
Objective: find prime factorization and greatest common factor
Bellwork
• Get with a partner.
• Take turns selecting dominoes.
• Your side is the base and your
partner's side is the exponent.
• Write problem in TicTacToe box.
• Find the answer.
Nov 18­3:12 PM
HW pg. 185 #6­36 evens, 40­42
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2. 4.3 Prime Factors
October 17, 2013
Prime Numbers: an integer greater than 1 with exactly 2
positive factors
Examples:
Composite Numbers: an integer greater than 1 with
more than 2 positive factors.
Examples:
Nov 18­3:14 PM
HW pg. 185 #6­36 evens, 40­42
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3. 4.3 Prime Factors
October 17, 2013
List the prime numbers from 10 to 20.
Nov 18­3:15 PM
HW pg. 185 #6­36 evens, 40­42
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4. 4.3 Prime Factors
October 17, 2013
Prime factorization: writing a composite number as a
product of its prime factors. We can use a factor tree to
find prime factorizations.
Use a factor tree to write the prime factorization of 825.
Nov 18­3:15 PM
HW pg. 185 #6­36 evens, 40­42
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5. 4.3 Prime Factors
October 17, 2013
Greatest Common Factor (GCF):
Use the prime factorization to find each GCF.
What do these numbers divide by? How do we know?
12,
87
Find the GCF of each pair of numbers or expressions.
40 and 60
6a3b and 4a2b
15m2n, 45m
Oct 16­2:51 PM
HW pg. 185 #6­36 evens, 40­42
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6. 4.3 Prime Factors
October 17, 2013
HW pg. 185
# 6­36 evens, 40­42
Nov 19­3:55 PM
HW pg. 185 #6­36 evens, 40­42
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