Solving Two-Step Equations

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Solving Two-Step Equations
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What is a Two-Step Equation?

• An equation that has 2 numbers on the same side
  of the variable
• 3x 7 13

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Examples of Two-Step Equations

1. 3x 5 16
2. y 3 12
3. 5n 4 6
4. n 6 4

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Steps for Solving Two-Step Equations

1. Solve for any ADDITION OR SUBTRACTION on the
   variable side of equation by undoing the
   operation from both sides of the equation.
2. Solve any MULTIPLICATION OR DIVISION from
   variable side of equation by undoing the
   operation from both sides of the equation.

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Opposite Operations

• Addition ?

• Subtraction

Multiplication ?
Division
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REMEMBER, When Solving Equations We Always

• Find the variable that needs to be alone.
• Figure out what numbers we need to get rid of.
• Whatever we do to one side, we must do to the
  other side to keep the equation balanced.

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Ex. 1 Solve 4x 5 15

• 4x 5 15
• 5 5
• 4x 20
• 4 4
• x 5

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WAIT!How do you know what to get rid of first?

• Pretend its a Party
• First your friend leaves
• Then your boyfriend or girlfriend leave

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Ex. 1 Solve 4x 5 15

• 4x 5 15
• 5 5
• 4x 20
• 4 4
• x 5

Friend, not touching
Boyfriend or Girlfriend, holding hands
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Try These Examples

• 2x 5 17
• 3y 7 25
• 2 5n 38
• 4 12b 28

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Try these examples!

1. x 3 8
2. c 4 9
3. 6 r 2
4. 4 d 5

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