Question

How do you prove theorems behind two parallel lines cut by a transversal?

Answer 1

@LieutenantGeneral

Answer 2

Say AB and CD are the two parallel lines cut by a transversal at E and F respectively.

Then the pairs of alternate interior angles are:
Angle(AEF) and Angle(DFE)
Angle(CFE) and Angle(BEF)

Proof:

Angle(CFE) +Angle(DFE) = 180
(linear pair)
Also,
Angle(CFE) +Angle(AEF) = 180
(Corresponding angles)

Equate the above results:
Angle(CFE) +Angle(DFE) = Angle(CFE) +Angle(AEF)

<=> Angle(DFE) = Angle(AEF)

Similarly,
Angle(CFE) = Angle(BEF)

Answer 3

How would I say that verbally without an example. It's an example of what could be asked during my verbal assessment