Page 45 - Math Course 1 (Book 1)

Algebraic Equations

Mo. 1

Lesson 8

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

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

Arithmetic Sequences:
Finding Terms

Vocabulary A-Z Let’s Begin

Let us learn some vocabulary

Describe an Arithmetic Sequence

Sequence
is an ordered list of numbers. Example
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

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

Arithmetic sequence
is a sequence in which the difference between any
two consecutive terms is the same
20, 30, 40, 50, 60,

+10 +10 +10 +10

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