Difference between revisions of "Equilateral Triangle Theorem"

(A stub about a geometric theorem)
 
 
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==Proof==
 
==Proof==
  
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Assume a triangle ABC of equal sides AB, BC, and CA.  By the ITT (Isosceles Triangle Theorem), m∠ABC = m∠BCA, m∠BCA = m∠CAB, and m∠CAB = m∠ABC.<ref>Euclid.  ''The Elements''.  Book I.
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Assume a triangle ABC of equal sides AB, BC, and CA.  By the ITT (Isosceles Triangle Theorem), m∠ABC = m∠BCA, m∠BCA = m∠CAB, and m∠CAB = m∠ABC.<ref>Euclid.  ''The Elements''.  Book I.</ref>
  
 
==See also==
 
==See also==

Latest revision as of 00:02, March 3, 2017

The Equilateral Triangle Theorem is a theorem which states that if all three sides of a triangle are equal, then all three angles are equal. It is a corollary of the Isosceles Triangle Theorem.

Proof

Assume a triangle ABC of equal sides AB, BC, and CA. By the ITT (Isosceles Triangle Theorem), m∠ABC = m∠BCA, m∠BCA = m∠CAB, and m∠CAB = m∠ABC.[1]

See also

References

  1. ↑ Euclid. The Elements. Book I.