What’s the correct answer for this?

Answer:
20
Step-by-step explanation:
Since chord AB and DE are at equal length from the centre, they are equal in length.
AB = DE
3x-7 = 5(x-5)
3x-7 = 5x-25
-7+25 = 5x -3x
18 = 2x
Dividing both side by 2
x = 9
Now
AB = 3(9)-7
= 27 -7
= 20