Use the diagram shown.

Two intersecting lines form four angles, 1, 2, 3, and 4. Angles 1 and 2 are adjacent angles and angles 1 and 3 are vertical angles.

If m∠1 = (4x + 2) and m∠3 = (5x – 15), what is the value of x?
A. 14
B. 15
C. 16
D. 17