Grade 7 Mathematics Module 2, Topic A, Lesson 5

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Student Outcomes

  • Students justify the rule for subtraction:  Subtracting a number is the same as adding its opposite.
  • Students relate the rule for subtraction to the Integer Game:  removing (subtracting) a positive card changes the score in the same way as adding a corresponding negative card.  Removing (subtracting) a negative card makes the same change as adding the corresponding positive card.
  • Students justify the rule for subtraction for all rational numbers from the inverse relationship between addition and subtraction; i.e., subtracting a number and adding it back gets you back to where you started: (m - n) + n = m.


Downloadable Resources

Common Core Learning Standards

CCLS State Standard
7.NS.1.b Understand p + q as the number located a distance |q| from p, in the positive or negative direction...

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