Answer:
AB = 23.4 inches
Explanation:
If the diameter of the wheel is 25 inches, we have that its radius is 25/2 = 12.5 inches.
If we draw a radius to the bottom of the wheel and a radius to point A, we have a triangle where we can use Pythagoras' formula:
(see image attached for better understanding)
r^2 = (r-8.1)^2 + (AB/2)^2
12.5^2 = 4.4^2 + AB^2/4
156.25 = 19.36 + AB^2/4
AB^2/4 = 136.89
AB^2 = 547.56
AB = 23.4 inches