Angles ∠EFC and ∠EFD, formed when lines AB and CD intersect at point F and ray FE forms a right angle, are known as vertical angles. This is due to their position across from one another at the intersection.
The best description for the angle relationship between ∠EFC and ∠EFD is that they are vertical angles. When two lines intersect each other, like AB and CD at point F, four angles are formed. Among these angles, the ones that are across from each other are called vertical angles.
In this case ∠EFC and ∠EFD, the angles opposite each other at point F,is called vertical angles. Vertical angles are equal irrespective of the length of the intersecting lines. So, the main answer in 2 lines is that angles ∠EFC and ∠EFD are vertical angles.
In conclusion, the relationship between angles ∠EFC and ∠EFD when lines AB and CD intersect at F, forming a right angle ∠EFB with ray FE, is that they are vertical angles.
Learn more about Vertical Angles