i dont know how to solve this

Answer:
Step-by-step explanation:
Given,
x + ( x + 8) + 2x = 180° [Since angle sum property of triangle]
=> x + x + 8 + 2x = 180
=> 4x + 8 = 180
=> 4x = 180 - 8
=> 4x = 172
[tex] = > x = \frac{172}{4} [/tex]
=> x = 43
As,
We got value of x as 43 so,
x° = 43°
x° = 43 + 8 = 51°
x° = 2 × 43 = 86°