View source for Geometry for Elementary School/The Side-Angle-Angle congruence theorem

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In this chapter, we will discuss yet another congruence theorem, the Side-Angle-Angle congruence theorem, usually abbreviated as SAA(or AAS - Angle-Angle-Side , commonly used in India)
== The Angle-Side-Angle congruence theorem ==
Given two triangles <math>\triangle ABC </math> and <math>\triangle DEF </math> such that their sides are equal, hence:[[File:AAS example.png]]
# The angle <math>\angle CAB </math> equals <math>\angle FDE </math>.(they have the same angle <math>x </math>)
# The angle <math>\angle ABC </math> equals <math>\angle DEF </math>.(they have the same angle <math>z </math>)
# The side <math>\overline {BC} </math> equals <math>\overline {EF} </math>.(they have the same side <math>y </math>)

Then the triangles are congruent and their other angles and sides are equal too.