Theory:

While, subtraction of \(2\) integers, depending upon the sign of the two or more integers, the answer can change.
  
Subtraction on integers:
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. Find the value: 5+9 
 
The given expression is (\(-5\)) and (\(9\)) since these numbers have different signs, so the difference of the numbers are taken, and the answer will have the sign of a larger number.
 
Hence the answer is \(+4\).
 
Further examples:
 
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. \(20 - 48 = -28\)