Answer:
x = 28
Step-by-step explanation:
If AB and CD are the straight lines, sum all the angles formed at a point lying on this line will be 180°.
m∠COE + m∠EOF + m∠FOB + m∠BOD = 180° [Angles at a point O on line AB]
3x + x + (x + 12) + m∠BOD = 180°
m∠BOD = 180° - (5x + 12)
Similarly, m∠AOD + m∠AOC = 180°
152° + m∠AOC = 180°
m∠AOC = 28°
Since, ∠AOC and ∠BOD are the vertical angles,
m∠AOC = m∠BOD
180° - (5x + 12)° = 28°
5x + 12 = 180 - 28
5x = 140
x = 28
