Page 36 - Math Course 2 (Book 1)

Algebraic Equations

Mo. 1

Lesson 8

Common difference
KEY CONCEPTS:
1. Describe sequences using words and The difference between the terms of a sequence is
symbols. called the common difference.
2. Find terms of arithmetic sequences. 20, 30, 40, 50, 60, ...

+10 +10 +10 +10
MO. 1 - L8a ( +10 is the common difference )

Arithmetic Sequences:
Finding Terms

Vocabulary A-Z Let’s Begin
Let us learn some vocabulary

Describe an Arithmetic Sequence

Sequence
Example
is an ordered list of numbers.

3 7 11 15 19 23 Describe the sequence 3, 6, 9, 12, … using
words and symbols.

+1 +1 +1

Term Number
1 2 3 4
(n)

Term (t) 3 6 9 12

Arithmetic sequence

is a sequence in which the difference between any +3 +3 +3
two consecutive terms is the same.

20, 30, 40, 50, 60, Answer
The difference of the term numbers is 1. The
terms have a common difference of 3. Also, a
+10 +10 +10 +10
term is 3 times the term number. The equation
t = 3n describes the sequence.
Term

Each number is called a term of the sequence.
20, 30, 40, 50, 60,... 20,30,40,50,60
are terms of
+10 +10 +10 +10 this sequence.

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