Answer:
a.1
b. 17
Explanation:
So the | | around an equation makes it an absolute value which can be defined as the "distance from zero" or in other words, if a value is positive, it stays positive, and if a value is negative, it becomes positive.
|-8 + 9| = |1| = 1
|-8| + 9 = 8 + 9 = 17