Transcript over Lesson 9–1

Five-Minute Check (over Lesson 9–1)
Main Idea and Vocabulary
Example 1: Use Models
Example 2: Use Factor Pairs
Example 3: Find the Prime Factorization
of a Number
• I will identify prime and composite numbers.
• prime factorization
Use Models
Tell whether the
number 14 represented
by the model is prime
or composite.
The model shows 2 rows of 7 squares. The squares
could also be arranged in 7 rows of 2 squares, 14 rows
of 1 square, or 1 row of 14 squares, as shown below.
Answer: So, the number 14 is a composite number
because it has more than 2 factors.
Tell whether the number 8 represented by the
model is prime or composite.
A. prime
B. composite
1.
2.
m
po
si
te
0%
co
pr
im
e
0%
A
B
Use Factor Pairs
19 square tables are to be placed together to
form a rectangle. Is 19 a prime or composite
number? What does it mean in this problem?
factors of 19: 1, 19
Answer: Since the number 19 only has two factors,
it is a prime number. This means there is
only one way to place the tables.
24 tables are to be placed together to form a
rectangle. Is 24 a prime or composite number?
A. prime
B. composite
1.
2.
0%
A
0%
B
A
B
Find the Prime Factorization of a Number
Find the prime factorization of 54.
54
54
2 × 27
3 × 18
2×3 × 9
3×3 × 6
2×3×3×3
3×3×3×2
Answer: In order, the prime factorization of 54 is
2 × 3 × 3 × 3.
Which shows the prime factorization of 81?
A.
2×3×3
B.
2×2×3×9
C.
3×3×3×3
D.
9×9
0%
0%
A
B
1.
2.
3.
4.
0%
C
A
B
C
D
0%
D
End of the Lesson
Five-Minute Check (over Lesson 9–1)
Image Bank
Math Tool Chest
Compare Fractions
(over Lesson 9–1)
Find the common factors of 12 and 18.
A. 1, 2, 3, 6, 9
B. 1, 2, 3, 4, 6, 9
C. 1, 2, 3, 6
D. 6, 9
0%
0%
A
B
1.
2.
3.
4.
0%
C
A
B
C
D
0%
D
(over Lesson 9–1)
Find the common factors of 20, 24, and 28.
A. 1, 2, 4
B. 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14
C. 1, 2, 3, 4, 6, 12, 14
D. 2, 4
0%
0%
A
B
1.
2.
3.
4.
0%
C
A
B
C
D
0%
D
(over Lesson 9–1)
Find the GCF of 15 and 20.
A. 4
B. 5
C. 3, 5
D. 1, 5
0%
0%
A
B
1.
2.
3.
4.
0%
C
A
B
C
D
0%
D
(over Lesson 9–1)
Find the GCF of 21, 28, and 35.
A. 1, 3, 4, 6, 7
B. 3
C. 1, 7
D. 7
0%
0%
A
B
1.
2.
3.
4.
0%
C
A
B
C
D
0%
D