Integer addition: Problem type 2
If the signs of the integers are same, we add the numbers and keep the sign
If the signs are positive, we add the numbers and keep the positive sign.
If the signs are negative, we add the numbers and keep the negative sign.
If the signs are different, we subtract the numbers and keep the sign of the number with larger absolute value.
Add
23 + (−36)
Solution
Step 1:
The signs of the numbers are different. So, we subtract the absolute values of the integers.
|−36| – |23| = 36 – 23 = 13
Step 2:
The sign of the number with larger absolute value (−36) is −.
We keep this sign with the difference obtained in above step
So, 23 + (−36) = − 13
Add
−45 + (−58)
Solution
Step 1:
The signs of the numbers are same. So, we add the absolute values of the integers.
|−45| +| − 58| = 45 + 58 = 103
Step 2:
The common sign of both numbers is −.
We keep this sign with the sum obtained in above step
So, −45 + (−58) = − 103