Answer:
x = 52/9
Step-by-step explanation:
The exterior angle is half the difference of the intercepted arcs, so we have ...
9x -5 = (158 -64)/2
9x = 52 . . . . . . . . . . . add 5
x = 52/9 = 5 7/9
For this case we must complete squares:

We add the square of half the coefficient of the term "x",
on both sides of the equation:

According to the perfect square trinomial we have:

Rewriting the expression we have:

ANswer:

2 is the answer 23:35677544