Line segments AB and CD intersect at E. If m∠AEC = 3x + 12 and m∠CEB = 2x + 13, find all angles.

a) m∠AEC = 3x + 12, m∠CEB = 2x + 13
b) m∠AEC = 2x + 13, m∠CEB = 3x + 12
c) m∠AEC = 3x - 12, m∠CEB = 2x - 13
d) m∠AEC = 2x - 13, m∠CEB = 3x - 12