MHB Proving the Angle-Angle-Side Theorem

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The discussion centers on proving the Angle-Angle-Side (AAS) theorem, which states that if two triangles have two pairs of congruent angles and a congruent side between them, the triangles are congruent. Participants clarify that with two pairs of angles congruent, the third angle must also be congruent. The proof involves showing that the angles and the side meet the criteria for congruence, leading to the conclusion that the triangles are congruent by the Angle-Side-Angle (ASA) criterion. The conversation emphasizes the logical progression from angle congruence to triangle congruence. Understanding and applying these principles is essential for successfully proving the AAS theorem.
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Hello everyone. I need help on proofs. I have to proof the Angle-Angle-Side theorem. Can someone help me with this?

The AAS states : If triangles ABC and DEF are two triangles such that angle ABC is congruent to angle DEF, angle BCA is congruent to angle EFD, and segment AC is congruent to DF, then triangles ABC and DEF are congruent.

Thank You!
 
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pholee95 said:
Hello everyone. i have to proof the Angle-Angle-Side theorem.
Can someone help me with this?

The AAS states : If triangles ABC and DEF are two triangles such that angle ABC is congruent to angle DEF,
angle BCA is congruent to angle EFD, and segment AC is congruent to DF,
then triangles ABC and DEF are congruent.
Since two pairs of angles are congruent, the third pair is also congruent.
. . That is: \angle BAC = \angle EDF.

We have: \angle ACB = \angle DFE.\;AC = DF,\;\angle BAC = \angle EDF.

The triangles are congruent by ASA.

.
 
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