Math B Unit 2 Study Guide

1
Math B Unit 2 Study Guide

• Exponents and Scientific Notation
• Formulas and Expressions
• Integers/Absolute Value
• Equations and Inequalities with Integers

2
Exponents
Key points to remember about exponents
3
6
6x6x6 216
It does NOT equal 6 x 3 18
Negative exponents are simply fractions
1
1
-3
1
7



7x7x7
343
3
7
3
Formulas and Expressions
Remember to use the order of operations when
simplifying or evaluating expressions
Remember when you have a choice of multiplication
and division, you should work from left to right.
P E M D A S
arenthesis
xponents
Example 16 4 x 2 Do the 16 4 first. Then 4
x 2
ultiplication
ivision
ddition
The same is true for addition and subtraction
ubtraction
4
Integers
Rules for addition 1. If the signs are the same,
keep the sign and add.
Example -13 -20 -33
2. If the signs are different, keep the sign of
the one farthest from zero and subtract.
Example -20 12 -8
On a number line, -20 would be farther from zero
than positive 12, so we keep the negative sign
for the answer. 20-12 8 So the answer is
negative 8.
5
Subtraction of Integers
Change the problem to addition by Adding the
Opposite, then follow the addition rules.
Example 16 ( 7)
Now it becomes 16 7 23
Example -13 5
Now the answer is -18
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Multiplication and Division of Integers
If the signs are the same, the answer is
positive. If the signs are different, t
he answer is negative.
-20 x -4 80
-15 x 3 -45
7
Solving Equations
y
x
When solving equations or inequalities, the
purpose is to isolate the variable in other
words, we want to get the variable all alone.
Thanks to Mr. Mascott, we joke about the variable
being a celebrity. In order to get the
celebritys autograph, you have to get the
celebrity alone.
n
8
Lets look at the following example
3y (-4) 19
Y is the celebrity
The 3 is the BODYGUARD
Subtracting negative 4 is the screaming fans.
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As a general rule, to get rid of anything, you do
the opposite to BOTH SIDES OF THE EQUATION.
The opposite of subtracting negative 4 is.
Adding negative 4
The opposite of multiplying by 3 is.
Dividing by 3
3y (-4) 19
10
3y (-4) 19
(-4) (-4)
Step 1 Add -4 to both sides. (This is getting
rid of the fans).
3y 15
3
3
Step 2 Divide both sides by 3. This is getting
rid of the bodyguard.
y 5
The y is by itself. You are now free to get your
autograph.
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Check back soon for more on inequalities.