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How To Cheat Sheet for Positive and Negative Numbers

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Here is your cheat sheet to help you remember what to do with positive and negative numbers (integers) with adding, subtracting, multiplying and dividing.
Time Required: 20 Minutes & Practice

Here's How:

  1. Adding Rules:

    Positive + Positive = Positive: 5 + 4 = 9
    Negative + Negative = Negative: (- 7) + (- 2) = - 9

    Sum of a negative and a positive number: Use the sign of the larger number and subtract

    (- 7) + 4 = -3
    6 + (-9) = - 3
    (- 3) + 7 = 4
    5 + ( -3) = 2

  2. Subtracting Rules:

    Negative - Positive = Negative: (- 5) - 3 = -5 + (-3) = -8
    Positive - Negative = Positive + Positive = Positive: 5 - (-3) = 5 + 3 = 8
    Negative - Negative = Negative + Positive = Use the sign of the larger number and subtract (Change double negatives to a positive)
    (-5) - (-3) = ( -5) + 3 = -2
    (-3) - ( -5) = (-3) + 5 = 2

  3. Multiplying Rules:

    Positive x Positive = Positive: 3 x 2 = 6
    Negative x Negative = Positive: (-2) x (-8) = 16
    Negative x Positive = Negative: (-3) x 4 = -12
    Positive x Negative = Negative: 3 x (-4) = -12

  4. Dividing Rules:

    Positive ÷ Positive = Positive: 12 ÷ 3 = 4
    Negative ÷ Negative = Positive: (-12) ÷ (-3) = 4
    Negative ÷ Positive = Negative: (-12) ÷ 3 = -4
    Positive ÷ Negative = Negative: 12 ÷ (-3) = -4

Tips:

  1. When working with rules for positive and negative numbers, try and think of weight loss or poker games to help solidify 'what this works'.
  2. Using a number line showing both sides of 0 is very helpful to help develop the understanding of working with positive and negative numbers/integers.

What You Need

  • Calculator
  • Free Worksheets Below
  • An Understanding of the 4 Operations
  • A Number Line
  • Pencil and Eraser
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