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Triangle Congruence

Triangle Congruence

Author: Jonathan Heeren
Description: Know and apply properties of congruent and similar figures to solve problems and logically justify results. 

a) I can recognize congruent figures and justify

    congruency of two triangles.

b) I can recognize similar figures.

c) I can calculate lengths in similar figures using

    proportional reasoning including real-world


d) I can logically justify the similarity of two triangles.

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5 ways to prove triangles are congruent

Please copy down these 5 ways to prove triangles congruent into your notes.

SSS, SAS, ASA, AAS theorems

This video shows how to prove 2 triangles are congruent using Side-Side-Side, Side-Angle-Side, Angle-Side-Angle, Angle-Angle-Side

Hypotenuse Leg theorem

This short video explains the only time that Side-Side-Angle theorem works (in a right triangle).

Proof Example

This is an example of a proof showing that 2 triangles are congruent.

Examples of Proofs

Here is another example of what a proof looks like

Geometry Proof Packet

This is page 2-3 of your proof packet that you received in class today. It is some examples to help you get started.

SSS and SAS congruent triangles


Triangle Congruence WS

Recognizing congruent triangles and why


Congruent Triangles


Fill in the blank proofs


Proofs of Congruent triangles

This is practice proving from start to finish