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IMAS 2017–2018 Junior Round 2 Question 2

IMAS · IMAS 2017–2018 Junior Round 2

Question 2

In convex quadrilateral $ABCD$, bisectors of $\angle DAB$ and $\angle ABC$ intersect at $E$, bisectors of $\angle BCD$ and $\angle CDA$ intersect at $F$, as shown in the figure below. If $\angle AEB=80^\circ$, what is the angle measure, in degrees, of $\angle DFC$?

Question illustration
  1. 80
  2. 90
  3. 100
  4. 110
  5. Undetermined.