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Intermediate Proof

Intermediate Proof

Author: Alex G

Students will be able to write congruent triangle proofs using the flow proof format and the statement-reason (two-column) format.

Demonstrates a congruent triangle proof in two different formats (statement-reason and flow proof).

Cover art of a maze was taken from the Morgue File website which grants permission for use of its images.

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The Proof

This packet shows two different ways of completing the following proof. 


The Flow Proof was completed using Angle-Side-Angle triangle congruence.  Before you view the video, try to figure out which angles were used and why they are congruent.

The Statement-Reason Proof was completed using Angle-Angle-Side triangle congruence, so different angles were used.  Which ones were they?

You can decide which proof makes more sense to you.

Flow Proof using Congruent Triangles

Proof using the flow proof format showing that two triangles are congruent and then showing corresponding part congruence.

Statement Reason Proof Using AAS

Same proof as above completed in the statement reason format, using AAS instead of ASA.