Two solutions exist,
2(x - 1) = 8
2x - 2 = 8
2x = 10
x = 5
&
2(x + 1) = 8
2x + 2 = 8
2x = 6
x = 3
the two solutions are 5 and 3
Answer is in the pic above. Theorems used:
Exterior angle theorem
Inscribed angle theorem.

Answer:
True, True, False
Step-by-step explanation:
12b+3=-2b-4
12b+2b=-4-3
14b=-7/:14
b=-7/(14)
b=-1/2