Tests are graded

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Tests are graded Check Aeries!New Homework
Stamp Logs Tomorrow ?
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Warmups
Multiply
Solve the system
3.
1.
Subtract
2.
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10-1 Factors and Greatest Common Factors

• Objective To find prime factorizations and
  greatest common factors for monomials.
• Standard 11.0

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Factors

• Factor a number or variable that divides evenly
  into your original number.
• Example 1 Find the factors of 72.
• 1 72
• 2 36
• 3 24
• 4 18
• 6 12
• 8 9
• This problem is like 19-23 in homework tonight!

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Some terms to know

• Prime Only factors are 1 itself
• Composite Having more than 2 factors
• Write the prime numbers up to 20
• 1, 2, 3, 5, 7, 11, 13, 17, 19

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FACTOR TREE (for composite s)

• 384
• 2 192
• 2 96
• 2 48
• 2 24
• 2 12
• 2 6
• 2 3

22222223
Prime factorization
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TOO

• 1) 20 2) 36
• 225 2233
• Hints
• If it is an even, it is divisible by 2
• If you add the digits and the answer is
  divisible by 3, then the original number is
  divisible by 3
• If it ends in 0 or 5, it is divisible by 5
• Stop trying when the answer is smaller than the
  number you divided by

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Factoring with Variables

• 81b2c3
• 9 9
• 3 3 3 3
• 3333bbccc
• TOO
• 32abc3
• 22222abccc

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Greatest Common Factor (GCF)

• Make a factor tree and multiply together what
  they have in common
• 80 28
• 2 40 2 14
• 2 20 2 7
• 2 10
• 2 5
• 22 4 GCF

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GCF Biggest number that will divide evenly into
all of the numbers

• With variables, take the smallest exponent
• 32xy2z, 48x3y4
• 22222, 22223
• GCF 16xy2
• TOO for Homework
• 18xp2, 48x4

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Challenge Problem find the GCF
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Homework

• Greatest Common Factor Worksheet

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Math Lab Warmups
Multiply
3.
1.
Subtract
2.
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Example 1 Using a Factor Tree to Find Prime
Factorization
Write the prime factorization of the number.
A. 24
Write 24 as the product of two factors.
24
8 3
Continue factoring until all factors are prime.
4 2 3
2 2 2 3
The prime factorization of 24 is 2 2 2 3.
Using exponents, you can write this as 23 3.
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Example 2 Using a Factor Tree to Find Prime
Factorization
Write the prime factorization of the number.
B. 150
150
Write 150 as the product of two factors.
30 5
Continue factoring until all factors are prime.
10 3 5
2 5 3 5
The prime factorization of 150 is 2 3 5 5,
or 2 3 52.
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Insert Lesson Title Here
Try This Example 3
Write the prime factorization of the number.
A. 36
Write 36 as the product of two factors.
36
18 2
Continue factoring until all factors are prime.
9 2 2
3 3 2 2
The prime factorization of 36 is 2 2 3 3.
Using exponents, you can write this as 22 32.
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Insert Lesson Title Here
Try This Example 4
Write the prime factorization of the number.
B. 90
90
Write 90 as the product of two factors.
45 2
Continue factoring until all factors are prime.
9 5 2
3 3 5 2
The prime factorization of 90 is 3 3 5 2,
or 2 32 5.
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Your turn! ?

• Prime Factorization Worksheet
• Use scratch paper to make your factor trees.
• Remember to list your factors in order from least
  to greatest.
• Work Individually
• Switch and grade when everyone is done ?