Transcript 8-12 Order of Operations

Order of Operations
8.2.1
Apply the order of operations
when calculating with rational
numbers
But first… Exponents
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The distance from the Earth to the Sun is
150,000,000 km.
The size of an amoeba is about 0.00006
meters.
Shortcut way to represent repeated
multiplication by the same number.
The parts of an Exponent
3
base number
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6
exponent
The base number is the number multiplied by itself
repeatedly.
The exponent tells you how many times you are multiplying.
Exponential
form
Expanded form
Answer
36 = 3 x 3 x 3 x 3 x 3 x 3 = 729
Practice
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Write out all the possible exponents for the
base 3. Start at the power of 4 and stop at
the power of 1.
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Include the exponential form, expanded form, and
answer.
Example:
31 = 3 = 3
32 = 3 x 3 = 9
What is the pattern you see?
It Should Look Like This…
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35 = 3x3x3x3x3 = 243
34 = 3x3x3x3 = 81
33 = 3x3x3 = 27
32 = 3x3 = 9
31 = 3 = 3
The Pattern: Dividing by 3!
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34 = 3x3x3x3 = 81
33 = 3x3x3 = 27
32 = 3x3 = 9
31 = 3 = 3
30 = 1
3-1 = 1/3
3-2 = 1/9
3-3 = 1/27
3-4 = 1/81
Again, mathematicians = lazy
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The distance from the Earth to the Sun is
150,000,000 km.
OR: 15 x 107 km
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The size of an amoeba is about 0.00006
meters.
OR: 6 x 10-5 meters
Now... Solve this
24 + (14 ÷ 7) x 8 – 5
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Many different ways of solving. Find 2
different ways to get 2 different answers.
Please Excuse My Dear Aunt Sally
Really. She can’t help it.
PEMDAS
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Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction
4
2
+ (14 ÷ 7) x 8 – 5
24 + 2 x 8 – 5
2x2x2x2 + 2 x 8 – 5
16 + 2 x 8 – 5
16 + 16 – 5
32 – 5
27