Solving Linear Equations

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Solving Linear Equations
with Multiplication
and Division
Section 7.4
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To solve an equation
is to isolate
the variable.
3
To isolate the variable
means to get it alone
on one side
of the equation.
4
Given the equation,
how do we isolate
the x?
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What number has to move to leave x alone on one
side of the equation?
6
What number has to move to leave x alone on one
side of the equation?
7
Say,
7
If we could
move the seven,
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If we could
move the seven,
the x would be isolated.
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The next question is,
how can we move the 7?
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What is the seven
doing in the equation?
Say,
dividing
x
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What operation
undoes division?
Say,
multiplication
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To move the 7,
we just need to multiply
both sides of the equation
by 7.
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Remember . . .
when you do something
to one side of an equation
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you have to do exactly
the same thing
to the other side.
15
When we simplify,
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When we simplify,
we will have our solution.
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To solve equations
that involve multiplication
you divide,
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To solve equations
that involve multiplication
you divide,
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and to solve equations
that involve division
you multiply.
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and to solve equations
that involve division
you multiply.
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Solving Equations with Multiplications and
Division

• Identify your variable
• Identify what you need to get rid of.
• Use the inverse operations
• WHAT YOU DO TO ONE SIDE, YOU MUST DO TO THE
  OTHER.
• Do the math

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Try these
1.
2.
3.
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NOTEBOOK

• Solving Equations using Multiplication and
  Division
• Identify your variable
• Determine if you need to multiply or divide
• What you do to one side you must do to the other.