Answer:
6
Step-by-step explanation:
We know:
If a ≤ b ≤ c are the sides of a triangle, then a + b > c.
We have a = x, b = 2x and c = 15 cm.
Therefore x ≤ 15 and 2x ≤ 15 ⇒ x ≤ 7.5
Therefore we have the inequality:
x + 2x > 15
3x > 15 divide both sides by 3
x > 5 and x ≤ 7.5
Finally x = 6
