Theory:

While, addition or subtraction of \(2\) integers, depending upon the sign of the two or more integers, the answer can change.
 
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When two integers have the same sign, the sign of the answer will be the same sign of the integers.
Example:
1. In the above example, (\(-3\)) and (\(-4\)) are added both the integers have -ve sign, hence answer is \(-7\).
2. \((-6) + (-5) = -11\)
3. \(10 + 12 = 22\)
4. \((-32) + (-14) = -48\)
5. \(90 + 10 = 100\)
When two integers have a different sign, the sign of the answer will be the sign of the largest integer and both numbers will be subtracted.
Example:
1. In the above example (\(-5\)) and (\(9\)), the difference of the numbers are taken, and the sign of answer is \(+ve\). Hence the answer is\(+4\).
2. \((-20) + 13 = -7\)
3. \(30 - 15 = 15\)
4. \(20 + (-10) = 10\)
5. \(-30 + 50 = 20\)
When two integers are subtracted, (\(+ve\))\(-\)(\(-ve\)), or (\(-ve\))\(-\)(\(-ve\)),  since \(-ve\) multiplied by \(-ve\) is \(+ve\), the operand between both numbers will be taken as \(+\).
Example:
1. \((-10) - (-10) = (-10) + 10 = 0\)
2. \((20) - (-10) = 20 + 10 = 30\)
3. \((-50) - (-15) = -50 + 15 = -35\)
4. \((25) - (-15) = 25 + 15 = 40\)
When two integers are subtracted, in this manner, (\(+ve\)) \(-\) (\(+ve\)), both integers should be subtracted, and the sign of the answer will be the sign of the highest integer.
Example:
1. \(30 - 10 = 20\)
2. \(40 - 12 = 28\)
3. \(10 - 50 = -40\)
4. \(20 - 48 = -28\)