can someone pls help and explain. i have a test tomorrow and iām stressing

Answer:
see below
Step-by-step explanation:
The segment addition postulate just means we can add two segments together ad get the big segment
Since G is between F and H
FG + GH = FH
6 + GH = 11
Subtract 6 from each side
6-6 + GH = 11-6
GH = 5