Download Section 1-1: Patterns and Expressions

1-1 Patterns and Expressions
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Identifying Patterns
Patterns can be represented using words,
diagrams, numbers, or algebraic expressions.
What is the next figure?
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Look at the figures from right to left.
What is the pattern?
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Try this on your own.
Draw the next figure.
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Numerical Pattern
What is the next number in the pattern
2, 4, 6, 8, ….
6, 3, 0, -3, ….
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Variable- a symbol, usually a letter that
represents one or more numbers
ex:
x
or
n
Numerical Expression- mathematical phrase that
contains numbers and operation symbols.
ex: 3+5
Algebraic Expressions- mathematical phrase that
contains one or more variables
ex: 3n+5
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Using Tables to help identify patterns
Input
Process Column
Output
1
0
2
1
3
2
4
3
5
n
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Input
Process Column
Output
1
5
2
9
3
13
4
17
5
n
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Expressing a Pattern with Algebra
How many toothpicks are in the 20th figure?
Figure
Number
(Input)
Process Column
Number of
Toothpicks
(output)
1
1(4)
4
2
2(4)
8
3
3(4)
12
n
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Patterns on Graphs
The graph shows the cost depending on the number of DVDs that you purchase.
What is the cost of purchasing 5
DVD’s?
10 DVD’s?
Input
(x value)
Process Column
Output
(y-value)
0
0
1
16
2
32
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Section 1-1 Overview
• Patterns- look at the figures or numbers from
left to right and identify the pattern.
• Variables are used in math to represent an
unknown number in equations and
inequalities.
• Using Input/Output tables can help you find
patterns.
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