Math A

Adding
Signed Numbers

 

Rules:
  When you add two numbers with the same signs,
    1.   add the absolute values, and
2.   write the sum (the answer) with the sign of the
      numbers.
  When you add two numbers with different signs,
    1.   subtract the absolute values , and
2.   write the difference (the answer) with the sign of
      the number having the larger absolute value.

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Examples:    Add :
 
1.  -9 + (-7) = -16

 

5.   6 + (-2) = 4
2.   –20 + 15 = -5

 

6.   (-21) + 21 = 0
3.   (-23) + (-7) = -30

 

7.   –3 + 8 = 5
4.   (+3) + (+5) = 8

 

8.   -9 + 6 = -3

9.  Add -9 and -5.  Answer:   -14

 

10.  Add (-7), (+3), and (-12).  Answer:  -16

 

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Roberts

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