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Topic: common core geometry proofs
Replies: 10   Last Post: Aug 1, 2014 11:41 AM

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Michelle Riley

Posts: 5
From: Burnt Hills, NY
Registered: 12/8/13
Re: common core geometry proofs
Posted: Jul 31, 2014 1:22 PM
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We are trying to put together the proofs and had a question about standard G.C0.9. It says to prove "when a transversal crosses parallel lines, alternate interior angles are congruent and corresponding angles are congruent."

What postulates can we use to prove these? Other than the lines being parallel, what else can we know is given?

Thank you!
Michelle Riley
Burnt Hills-Ballston Lake High School
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