Answer:
4 < c < 14
e. g : {5, 6, 7, 8, 9, 10, 11, 12, 13}
Explanation:
Let
a, b, c - lengths of sides of a triangle
then:
a + b > c
a + c > b
b + c > a.
We have
a = 5, b = 9
then
c < 5 + 9 → c < 14 (1)
5 + c > 9 subtract 5 from both sides
c > 4 (2)
9 + c > 4 subtract 9 from both sides
c > -5 (3)
From (1), (2) and (3) we have
c < 14 ∧ c > 4 ∧ c > -5 → 4 < c < 14