# Identical triangles

• If two sides of two triangles are equal, and if one of their angles (faced?) to the non-smaller side are equal, then the triangles are identical.

So if $$AB=A'B';AC=A'C';AB\leq BC;\angle B=\angle B'$$

#### I got it already. But you can write it if you want

Note by Páll Márton (no activity)
1 month ago

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There are only five ways to prove congruency: SSS, SAS, ASA, AAS, and RHS. The SSA congruency theorem is not valid for all triangles. This might help. Sal shows why the length should be bigger.

- 1 month ago

What is HL? Is it RHS? :)

- 1 month ago

Yes, try opening the link now

- 1 month ago

My teacher explained us, so I know :)

- 1 month ago

- 1 month ago

Thank you! I got it. But if we know some other information, then it can be the smaller. Upvoted :)

- 1 month ago

Its not necessary, the following two triangles are also congruent:

- 1 month ago

You should change the angles :)

I don't understand. Wait, I am making another picture.

- 1 month ago

Ok. I'm waiting. The marked angle should be A

These 2 are also congruent:

- 1 month ago