1.
for solve -2 - (-3) note that we distribute the sign - which is in the position before the parenthesis, and we obtain the following multiplication:
- times - = +
so we obtain :
-2 + 3
but since the addition (subtraction) in the real numbers is commutative (it can be done in any order) we rearrange the previous equation
-2 + 3 = 3 -2 = 1
So, we can conclude that
-2 -(-3) = 1
2.
for solve 2 + (-5) note that we distribute the sign + which is in the position before the parenthesis, and we obtain the following multiplication:
+ times - = -
so we obtain:
2 - 5 = -3
because we always put the sign of the greater number (in this case 5).