Answer:
x = 60 degrees
Explanation:
1. We know that a triangle has a total angle of 180. If we look at the image closely, triangle GEH can be found, and since we know two angles, which are 40 and 80, we can find the other angle. 180 - (40+80) = 60. Angle GEH is 60 degrees.
2. If angle GEH is 60 degrees, angle EFD will also be 60 degrees, since they have the same angle side. To prove this, we can use alternate interior angles. This means that if a line crosses two parallel lines, the inner angles made have the same size.
3. Since angle EFD is x, we can find that x is equal to 60 degrees.