Answer:
see explanation
Step-by-step explanation:
∠c = ∠ a = 47° ( vertical angles )
∠c and ∠b form a straight angle and are supplementary, thus
∠c + ∠b = 180, that is
47 + ∠b = 180 ( subtract 47 from both sides )
∠b = 133°
∠d = ∠b = 133° ( vertical angles )
That is a = c = 47° and b = d = 133°
The sum of the 4 angles = 133° + 47° + 47° + 133° = 360°
360° is the sum of the angles round a point , hence answer is correct
