The answer is 12 including both sides and angles.
When you cut a square piece of paper from one point to the opposite point it should make two triangles.
Thus each triangle has 3 sides and 3 angles so two triangles has 6 angles and 6 sides
So 12, sides and angles added together.
Answer:
x=21°. :Angles subtended by the same arc
y=42°. :180-(117+21),angles subtended by the same arc
39
Divide 78 by 2 to get 39 and add in to the number
