Answer:
- 13 - 23 = - 13 + (-23)
= -36
- 13 - (- 23) = - 13 + 23
= 10
Step-by-step explanation:
In any order of operation (i.e. addition, subtraction, multiplication, devision) the following rules apply for two values for instance <em>a </em>and <em>b </em>where <em>a > b </em>:
→ <em>If +a and +b then the final sign will be + (positive)</em>
→ <em>If +a and -b then the final sign will be + (positive) since a>b</em>
→ <em>If -a and +b then the final sign will be - (negative) since a>b</em>
→ <em>If -a and -b then the final sign will be - (negative)</em>
In the given question we have two cases.
Case 1:
- 13 - 23 = - 13 + (-23) <em>→ since it is given that we add a negative value of -23, therefore it keeps its sign (so this would be a negative addition i.e. adding two negative values)</em>
Thus we have:
- 13 - 23 = - 13 + (-23)
= -36
Case 2:
- 13 - (- 23) = - 13 + 23 <em>→ since we stated earlier that - and - gives positive sign (i.e. we subtract two negative values)</em>
Thus we have:
- 13 - (- 23) = - 13 + 23
= 10
<em>So we can see that: </em>
<em>Adding two Negative values gives a Negative value (Case 1)</em>
Subtracting two Negative values gives a Positive value (Case 2)
