Use this PowerPoint to review Patterns in preparation to your Unit 3 Test.

1. Patterns

2. Numerical Patterns A numerical pattern is a list of numbers that follow a predictable rule. Once you determine that rule, you can extend the pattern. The rule must work for every number in the list. think Look at the first number in the list below. What can I do to the first number to get the second number in the list? think Look at the second number in the list below. What can I do to the second number to get the third number in the list? 2, 4, 6, 8, 10, 12 Add 2 (2 + 2 = 4) Multiply by 2 (2 × 2 = 4) Add 2 (4 + 2 = 6) Add 2 (6 + 2 = 8) Add 2 (8 + 2 = 10) Add 2 (10 + 2 = 12)

3. Geometric Patterns A geometric pattern is a list of geometric shapes that follow a predictable rule. Once you determine that rule, you can extend the pattern. Assigning a letter of the alphabet to each type of shape can help you find the rule. think What comes next in this pattern? The pattern is an ABBB pattern. The next shape in this pattern is a trapezoid. A B B B A B B B A B B B A B B B

4. Arithmetic Sequence One type of numerical pattern is an arithmetic sequence . An arithmetic sequence is an ordered set of real numbers. Each number in a sequence is a term . In an arithmetic sequence, each term after the first term ( a 1 ) is found by adding a constant, called the common difference ( d ) to the previous term. + 6 + 6 + 6 + 6 Finding the n th Term ( a n ) in an Arithmetic Sequence term 1 2 3 4 5 Common Difference (d) symbols numbers numbers symbols a 1 3 3 + 0(6) a 1 + 0(d) a 2 9 3 + 1(6) a 1 + 1(d) a 3 15 3 + 2(6) a 1 + 2(d) a 4 21 3 + 3(6) a 1 + 3(d) a 5 27 3 + 4(6) a 1 + 4(d) Arithmetic Sequence ...n ... a n ... a n ...3 + (n – 1)(6) a 1 + (n – 1)(d) think

5. Arithmetic Sequence + 6 + 6 + 6 + 6 Finding the n th Term ( a n ) in an Arithmetic Sequence term 1 2 3 4 5 Common Difference (d) symbols numbers numbers symbols a 1 3 3 + 0(6) a 1 + 0(d) a 2 9 3 + 1(6) a 1 + 1(d) a 3 15 3 + 2(6) a 1 + 2(d) a 4 21 3 + 3(6) a 1 + 3(d) a 5 27 3 + 4(6) a 1 + 4(d) Arithmetic Sequence ...n ... a n ... a n ...3 + (n – 1)(6) a 1 + (n – 1)(d) think Find the 11th term in 3, 9, 15, 21, 27, ... a n = a 1 + (n – 1)(d) a 11 = 3 + (11 – 1)(6) a 11 = 3 + (10)(6) = ?

6. Arithmetic Sequence + 6 + 6 + 6 + 6 Finding the n th Term ( a n ) in an Arithmetic Sequence term 1 2 3 4 5 Common Difference (d) symbols numbers numbers symbols a 1 3 3 + 0(6) a 1 + 0(d) a 2 9 3 + 1(6) a 1 + 1(d) a 3 15 3 + 2(6) a 1 + 2(d) a 4 21 3 + 3(6) a 1 + 3(d) a 5 27 3 + 4(6) a 1 + 4(d) Arithmetic Sequence ...n ... a n ... a n ...3 + (n – 1)(6) a 1 + (n – 1)(d) think Find the 11th term in 3, 9, 15, 21, 27, ... a n = a 1 + (n – 1)(d) a 11 = 3 + (11 – 1)(6) a 11 = 3 + (10)(6) = 63

7. Geometric Sequence Another type of numerical pattern is a geometric sequence . A geometric sequence is an ordered set of real numbers. Each number in a sequence is a term . In a geometric sequence, each term after the first term ( a 1 ) is found by multiplying the previous term by a constant ( r ), called the common ratio . × 2 × 2 × 2 × 2 Finding the n th Term ( a n ) in a Geometric Sequence term 1 2 3 4 5 Common Ratio (r) symbols numbers numbers symbols a 1 5 5 × (2) 0 a 1 × r 0 a 2 10 5 × (2) 1 a 1 × r 1 a 3 20 5 × (2) 2 a 1 × r 2 a 4 40 5 × (2) 3 a 1 × r 3 a 5 80 5 × (2) 4 a 1 × r 4 Geometric Sequence ...n ... a n ... a n ... 5 × (2) (n–1) a 1 × r (n–1) think

8. Arithmetic Sequence + 6 + 6 + 6 + 6 Finding the n th Term ( a n ) in an Arithmetic Sequence term 1 2 3 4 5 Common Difference (d) symbols numbers numbers symbols a 1 3 3 + 0(6) a 1 + 0(d) a 2 9 3 + 1(6) a 1 + 1(d) a 3 15 3 + 2(6) a 1 + 2(d) a 4 21 3 + 3(6) a 1 + 3(d) a 5 27 3 + 4(6) a 1 + 4(d) Arithmetic Sequence ...n ... a n ... a n ...3 + (n – 1)(6) a 1 + (n – 1)(d) think Find the 11th term in 5, 10, 20, 40, 80, ... a n = a 1 × r (n – 1) a 11 = 5 × (2) 10 a 11 = 5 (1,024) = ? × 2 × 2 × 2 × 2 Finding the n th Term ( a n ) in a Geometric Sequence term 1 2 3 4 5 Common Ratio (r) symbols numbers numbers symbols a 1 5 5 × (2) 0 a 1 × r 0 a 2 10 5 × (2) 1 a 1 × r 1 a 3 20 5 × (2) 2 a 1 × r 2 a 4 40 5 × (2) 3 a 1 × r 3 a 5 80 5 × (2) 4 a 1 × r 4 Geometric Sequence ...n ... a n ... a n ... 5 × (2) (n–1) a 1 × r (n–1) think

9. Arithmetic Sequence + 6 + 6 + 6 + 6 Finding the n th Term ( a n ) in an Arithmetic Sequence term 1 2 3 4 5 Common Difference (d) symbols numbers numbers symbols a 1 3 3 + 0(6) a 1 + 0(d) a 2 9 3 + 1(6) a 1 + 1(d) a 3 15 3 + 2(6) a 1 + 2(d) a 4 21 3 + 3(6) a 1 + 3(d) a 5 27 3 + 4(6) a 1 + 4(d) Arithmetic Sequence ...n ... a n ... a n ...3 + (n – 1)(6) a 1 + (n – 1)(d) think Find the 11th term in 5, 10, 20, 40, 80, ... a n = a 1 × r (n – 1) a 11 = 5 × (2) 10 a 11 = 5 (1,024) = 5,120 × 2 × 2 × 2 × 2 Finding the n th Term ( a n ) in a Geometric Sequence term 1 2 3 4 5 Common Ratio (r) symbols numbers numbers symbols a 1 5 5 × (2) 0 a 1 × r 0 a 2 10 5 × (2) 1 a 1 × r 1 a 3 20 5 × (2) 2 a 1 × r 2 a 4 40 5 × (2) 3 a 1 × r 3 a 5 80 5 × (2) 4 a 1 × r 4 Geometric Sequence ...n ... a n ... a n ... 5 × (2) (n–1) a 1 × r (n–1) think

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