ASA Postulate

Postulates are very useful in the world of math because we do not need to prove that they''re true. We can use these facts to solve all kinds of problems much faster. One example is the ASA postulate, which stands for "angle-side-angle."

The ASA postulate, explained

The ASA postulate states that:

• If two angles and an included side of one triangle are congruent to two angles and an included side of another triangle, then the two triangles must be congruent.

To understand how this works, we need to define "congruence." Congruence is simply another word for equality in the world of math, although it applies specifically to geometry.

Visualizing the ASA postulate

The ASA postulate may make more sense if we visualize it:


As we can see, one triangle has two angles and an included side that are congruent to two angles and an included side of the second triangle. Therefore, these two triangles are congruent.

The symbol "≅" represents congruence. Here''s the formula for the ASA postulate:

If

, , and , then .

Topics related to the ASA Postulate

Triangles

AAS Postulate

SAS Postulate

Flashcards covering the ASA Postulate

Advanced Geometry Flashcards

Common Core: High School - Geometry Flashcards

Practice tests covering the ASA Postulate

Common Core: High School - Geometry Diagnostic Tests

Advanced Geometry Diagnostic Tests

Get more help with the ASA postulate

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