Answer:
√10
Step-by-step explanation:
The radius of the incircle of a triangle is:
r = √(s (s−a) (s−b) (s−c)) / s
where s is half the perimeter, s = (a + b + c) / 2.
s = (9 + 13 + 14) / 2
s = 18
r = √(18 (18−9) (18−13) (18−14)) / 18
r = √(18 × 9 × 5 × 4) / 18
r = √10
