Answer:
38.5
Step-by-step explanation:
The perimeter is found by
P = 2( l+w)
We know the width is 23, we are looking for the length
P = 2 (23+l)
The perimeter is 123
123= 2 (23+l)
Divide each side by 2
123/2 = 23+l
61.5 = 23+l
Subtract 23 from each side
61.5 -23 = l
38.5 = l
The length of AB = 38.5
