Because < ABC is an inscribed angle, we know that it's measure is 1/2 that of its intercepted arc, or arc ADC.
Therefore, we can set up the following equation.
(150) = 1/2 (4x + 4)
If we simplify the equation, we get:
150 = 2x + 2
148 = 2x
x = 74
Therefore, x = 74, or the first answer choice.
