Jack,
Are you dealing here with "absolute values"? Or are you dealing with another math operation? If you are dealing with absolute value:
|-23| + |50| is the same as asking what is the "absolute value of negative 23" plus "the absolute value of 50."
The absolute vale of |-23| is equal to 23. This is because the absolute value of any number is its "distance" (in numerical units) from the whole number "0".
An absolute value of any number can never result in a negative value.
The absolute value of |50| is equal to 50. Again, because it is 50 units away from "0" (zero).
Thus |-23| + |50| is the same as saying,
23 + 50 = 73.
73 is the answer.