33 Solving Equations by Multiplying or Dividing

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3-3 Solving Equations byMultiplying or Dividing

• Objective Solve equations using the
  multiplication and division properties of
  equality.

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5-Minute Check

• Solve each equation.
• x 3 5

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5-Minute Check

• Solve each equation.
• x 3 5 8

4
5-Minute Check

• Solve each equation.
• x 3 5
• y 9 7

5
5-Minute Check

• Solve each equation.
• x 3 5
• y 9 7 -2

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5-Minute Check

• Solve each equation.
• x 3 5
• y 9 7
• 13 m 6

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5-Minute Check

• Solve each equation.
• x 3 5
• y 9 7
• 13 m 6 19

8
5-Minute Check

• Solve each equation.
• x 3 5
• y 9 7
• 13 m 6
• n (-1) 1

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5-Minute Check

• Solve each equation.
• x 3 5
• y 9 7
• 13 m 6
• n (-1) 1 0

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5-Minute Check

• Solve each equation.
• x 3 5
• y 9 7
• 13 m 6
• n (-1) 1
• f 4 -5

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5-Minute Check

• Solve each equation.
• x 3 5
• y 9 7
• 13 m 6
• n (-1) 1
• f 4 -5 -9

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3-3 Solving Equations by Multiplying or Dividing
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3-3 Solving Equations by Multiplying or Dividing
Example Solve 8y 96. Check your solution.
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3-3 Solving Equations by Multiplying or Dividing
Example Solve 8y 96. Check your solution. 8y/8
96/8 Divide each side by 8.
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3-3 Solving Equations by Multiplying or Dividing
Example Solve 8y 96. Check your solution. 8y/8
96/8 Divide each side by 8. y 12
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3-3 Solving Equations by Multiplying or Dividing
Example Solve 8y 96. Check your solution. 8y/8
96/8 Divide each side by 8. y 12 Check 8y
96 Replace y with 12.
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3-3 Solving Equations by Multiplying or Dividing
Example Solve 8y 96. Check your solution. 8y/8
96/8 Divide each side by 8. y 12 Check 8y
96 Replace y with 12. 8(12) ? 96
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3-3 Solving Equations by Multiplying or Dividing
Example Solve 8y 96. Check your solution. 8y/8
96/8 Divide each side by 8. y 12 Check 8y
96 Replace y with 12. 8(12) ? 96 96 96 The
solution is 12.
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3-3 Solving Equations by Multiplying or Dividing
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3-3 Solving Equations by Multiplying or Dividing
Example 2 Solve y/-6 12. Check your solution.
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3-3 Solving Equations by Multiplying or Dividing
Example 2 Solve y/-6 12. Check your
solution. -6 y/-6 -6 12 Multiply each side
by 6
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3-3 Solving Equations by Multiplying or Dividing
Example 2 Solve y/-6 12. Check your
solution. -6 y/-6 -6 12 Multiply each side
by 6 y -72
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3-3 Solving Equations by Multiplying or Dividing
Example 2 Solve y/-6 12. Check your
solution. -6 y/-6 -6 12 Multiply each side
by 6 y -72 Check y/-6 12 Replace y with
-72
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3-3 Solving Equations by Multiplying or Dividing
Example 2 Solve y/-6 12. Check your
solution. -6 y/-6 -6 12 Multiply each side
by 6 y -72 Check y/-6 12 Replace y with
-72 -72/-6 ? 12
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3-3 Solving Equations by Multiplying or Dividing
Example 2 Solve y/-6 12. Check your
solution. -6 y/-6 -6 12 Multiply each side
by 6 y -72 Check y/-6 12 Replace y with
72. -72/-6 ? 12 12 12 The solution is
72.
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3-3 Solving Equations by Multiplying or Dividing
Application Tom has a piece of rope that is 105
feet long. He wants to cut the rope into 5 equal
pieces. How long will each piece be?
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3-3 Solving Equations by Multiplying or Dividing
Application Tom has a piece of rope that is 105
feet long. He wants to cut the rope into 5 equal
pieces. How long will each piece be? Let L
represent the length of each piece.
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3-3 Solving Equations by Multiplying or Dividing
Application Tom has a piece of rope that is 105
feet long. He wants to cut the rope into 5 equal
pieces. How long will each piece be? Let L
represent the length of each piece. 105
5L Write an equation.
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3-3 Solving Equations by Multiplying or Dividing
Application Tom has a piece of rope that is 105
feet long. He wants to cut the rope into 5 equal
pieces. How long will each piece be? Let L
represent the length of each piece. 105
5L Write an equation. 105/5 5L/5 Divide
each side by 5.
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3-3 Solving Equations by Multiplying or Dividing
Application Tom has a piece of rope that is 105
feet long. He wants to cut the rope into 5 equal
pieces. How long will each piece be? Let L
represent the length of each piece. 105
5L Write an equation. 105/5 5L/5 Divide
each side by 5. 21 L The solution is 21.