Equations and Mental Math

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Equations and Mental Math

• 1.5

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Objective

• You will be able to use mental math to solve an
  equation!
• Word Watch
• - equation
• - solution
• - solving an equation

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Chip activity
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• In this activity, you solved equations by
  modeling with chips.
• An equation is a mathematical sentence formed by
  setting two expressions equal.
• A solution of an equation is a number that you
  can substitute for a variable to make an equation
  true. (The answer!)

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Checking Possible Solutions

• Tell whether the value is a solution of n 5
  12
• a) n 9 b) n 7
• a) n 5 12
• 9 5 12
• 14 12

b) n 5 12
?
?
7 5 12
12 12
/
TRUE!
NOT TRUE!
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? YOUR TURN!! ?

• Tell whether the value of the variable is a
  solution of the equation
• 7 13 n n 5
• NO!!! 13- 5 8!!!

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• Finding all solutions of an equation is called
  solving the equation.
• You can use mental math to solve simple equations
  by thinking of the equation as a question.

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Using Mental Math to Solve Equations
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Using Mental Math to Solve Equations
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Using Mental Math to Solve Equations
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Using Mental Math to Solve Equations
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Using Mental Math to Solve Equations
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Using Mental Math to Solve Equations
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? YOUR TURN!! ?

• Solve the equation using mental math!
• 7x 35
• What times 7 equals 35?
• 5
• 7 x 5 ?? check
• 35

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Distance formula!

• d rt
• Distance rate X time

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THOUGHT OF THE DAY!!

• Our eyes are always the same size from birth, but
  our nose and ears never stop growing.