I really need help find x in this triangle

Answer:
x = 5
Step-by-step explanation:
The sum of the 3 angles in a triangle = 180°
Sum the 3 angles and equate to 180
72 + 6x + 2 + 17x - 9 = 180
23x + 65 = 180 ( subtract 65 from both sides )
23x = 115 ( divide both sides by 23 )
x = 5