One Step Equations

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One Step Equations

• Essential Question How are inverse operations
  used to solve one step equations?

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Equations vs. Expressions
Equation Expression
An equation is a SENTENCE. Solve an equation. An equation HAS a equals symbol. Ex. Ten is five less than a number. 10 x - 5 A number is five. x 5 An expression is a PHRASE, a sentence fragment. Simplify an expression. An expression HAS NO equals symbol. Ex. a number less than fivex five less than a numberx 5
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Important Information
Inverse Operations Addition -gt Subtract Subtraction -gt Add Multiplication -gt Divide Division -gt Multiply Variable A letter or symbol that represents an unknown value usually represented with an x or y.
Zero pairs pair of numbers or operations that equal zero. Goal isolate the variable (use inverse operations to get the variable by itself.)
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The equation h 14 82 can be represented as a
balanced scale.
To find the value of h, you need h by itself on
one side of the scale.
To get h by itself, first take away 14 from the
left side of the scale. Now the scale is
unbalanced.
To rebalance the scale, take away 14 from the
other side.
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Taking away 14 from both sides of the scale is
the same as subtracting 14 from both sides of the
equation.
h 14 82
14
14
h 68
Subtraction is the inverse, or opposite, of
addition. If an equation contains addition, solve
it by subtracting from both sides to undo the
addition.
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Example

• x 4.5 7
• - 4.5 - 4.5
• x 2.5

• 7.0
• 4.5
• 2.5

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X

• What is the inverse operation of the equation
  above?
• Add
• Subtract
• Multiply
• Divide

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X

• What is the value of x?
• 1

9
X 6

• What is the value of x in the equation above?
• 6.75
• 7