Diana and Joby wrote the following proofs to prove that vertical angles are congruent. Who is correct?

Diana's Proof

Statement Justification
∠1 + ∠2 = 180° Definition of Supplementary Angles
∠1 + ∠4 = 180° Definition of Supplementary Angles
∠1 + ∠2 = ∠1 + ∠4 Transitive Property of Equality

Joby's Proof

Statement Justification
∠2 = ∠4 Vertical angles are congruent.
∠1 = ∠3 Vertical angles are congruent.
Vertical angles are congruent. Vertical Angle Theorem

Question

Diana and Joby wrote the following proofs to prove that vertical angles are congruent. Who is correct? 

Diana's Proof

Statement	Justification
∠1 + ∠2 = 180°	Definition of Supplementary Angles
∠1 + ∠4 = 180°	Definition of Supplementary Angles
∠1 + ∠2 = ∠1 + ∠4	Transitive Property of Equality


Joby's Proof

Statement	Justification
∠2 = ∠4	Vertical angles are congruent.
∠1 = ∠3	Vertical angles are congruent.
Vertical angles are congruent.	Vertical Angle Theorem

anonymous · Answer

attachment

cwrw238 · Answer

joby's answer is not a proof its just a statement

anonymous · Answer

yeah i knew that Diana's was right, but i wasn't sure about Joby because they didn't put anything like that in class. Thanks for your help clearing my doubts :)

cwrw238 · Answer

no probs