If two parallel lines are cut by a transverse, then the sum of the two exterior angles on one side of the traversal is what?

Question

mathstudent55 · Answer

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anonymous · Answer

so 180 degree?

mathstudent55 · Answer

Since the lines are parallel, angles 1 and 3 are congruent because they are corresponding angles. So m<1 = m<2
Angles 2 and 3 are supplementary, so m<2 + m<3 = 180
Therefore by substitution, m<2 + m<1 = 180

mathstudent55 · Answer

Yes, you're right

anonymous · Answer

I'm getting a bit better at geometry!!! yay:) No it's time to focus more on traversals and proofs

mathstudent55 · Answer

That's good. If you have questions, post them.

anonymous · Answer

I'm about to post one about finding angles in a traversal

mathstudent55 · Answer

ok, I'll look for it.