SAS Postulate

SAS stands for "side-angle-side." A "postulate" is something that is assumed true without anyone needing to validate it. Let''s find out why the SAS postulate is so useful:

The definition of the SAS postulate

The SAS postulate states that if one triangle''s two sides and included angle are congruent to a second triangle''s two sides and an included angle, then both triangles are congruent.

But what exactly is congruence? This is essentially just another way of saying "equal" in the world of geometry.

Consider these two triangles:

We can see that the SAS postulate applies in this situation. Therefore, the two triangles are congruent.

The formula for the SAS postulate is:

If

AB ≅ DE

and

BC ≅ EF

, and

∠B ≅ ∠E

, then

ΔABC ≅ ΔDEF

. Remember, the symbol "≅" represents congruence.

Topics related to the SAS Postulate

Triangles

Scale Drawings

ASA Postulate

Flashcards covering the SAS Postulate

Basic Geometry Flashcards

Common Core: High School - Geometry Flashcards

Practice tests covering the SAS Postulate

Common Core: High School - Geometry Diagnostic Tests

Intermediate Geometry Diagnostic Tests

Get more help with the SAS postulate

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