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Proof (harder)

Proof (harder)

Author: Dan Bowler

To demonstrate a flow proof and a two-column proof that involve several steps.

This lesson presents proof using a multistep problem that requires students to make some connections from various parts of the geometry curriculum. Both flow proof and two column formats are presented.

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This lesson provides students with an opportunity to work through a more lengthy geometric proof.  It is designed for students who have demonstrated some level of proficiency in mathematics and want to challenge themselves a bit .


A familiarity with triangle congruence and properties of quadrilaterals is assumed.


We will work through the proof in both flow proof form and two column form.

Flow Proof

A multistep flow proof is demonstrated.

Two-column proof

This video demonstrates a two-column proof with multiple steps.