Answer:
L = 15.53 ft
Step-by-step explanation:
using diagram which is attached below
now, using Pythagoras theorem
L² = b² + (5 + x)²...............(1)
using similarity of triangle
from equation (1)
for maxima or minima
x = -5 and x = ∛190 = 5.74
on second derivative 5.74 is the value which comes out to be minimal value which is the distance between the fence and ladder
now,
L² = 241.38
L = 15.53 ft
