What is the measure of n?

Answer:
n = √108 or 6√3
Step-by-step explanation:
n is the altitude of the right triangle
Based on the right triangle altitude theorem, we would have:
h = √(xy)
Where,
h = n
x = 18
y = 6
Substitute
n = √(18*6)
n = √108
Or
n = 6√3