Participation Project Quiz Complete the paragraph proof below.
Vertical Angles Theorem
If two angles form a pair of vertical angles, then they are congruent.
Given 1 and 23 are vertical angles.
Prove 223
You are given that 21 and 23 are vertical angles.
Because of the definition of a (1).
21 and 22 form a (1)
and
22 and 23 form a (1)
By the (1) postulate, m_1+m22=180° and mz2+m23=180".
By using the 21 property of equality and substituting m22+m23 for 180°
into the first equation, you get m_1+m22-m22+m23.
By using the 3)
property of equality, you can subtract m22 from both
sides to get m21=m23.
Because of the definition of congruent angles, (4)