Which of the following is a valid reason for stating that

Question

Which of the following is a valid reason for stating that <1  is congruent <2.
 A. Angles 1 and 2 are supplementary angles 
 B. Angles 1 and 2 are corresponding angles 
 C. Angles 1 and 2 are vertical angles 
 D. Angles 1 and 2 are alternate interior angles

anonymous · Answer

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anonymous · Answer

Angles 1 and 2 are vertical angles 

Vertically opposite angles are congruent.

cwrw238 · Answer

thats a curious term vertically opposite - why not just opposite?

anonymous · Answer

so do you think he is wrong?

cwrw238 · Answer

no - he is dead right right - i find the description 'vertical'  curious thats all

anonymous · Answer

Hey cwrw238! They are the same thing. "In geometry, a pair of angles is said to be vertical (also opposite and vertically opposite, which is abbreviated as vert. opp. ∠s[1]) if the angles are formed from two intersecting lines and the angles are not adjacent. " http://en.wikipedia.org/wiki/Vertical_angles