Answer:
x = 17
Step-by-step explanation:
SOLUTION,
Let the sides of the triangle be ∠ABC= 5x , ∠BAC=(2x+6) and ∠ACD= (8x-11)
Since the exterior angle of a triangle is the sum of two opposite interior angles
NOW,
∠ACD=∠ABC+∠BAC
⇒8x-11 = 5x + (2x+6)
⇒8x -11= 5x + 2x +6
⇒8x - 11 = 7x +6
⇒8x - 7x = 11 +6
⇒x = 17
