Euclid:

If two triangles have two sides equal to two sides respectively, and have the angles contained by the equal straight lines equal, they will also have the base equal to the base, the triangle will be equal to the triangle, and the remaining angles will be equal to the remaining angles respectively, namely those which the equal sides subtend.

— Euclid Ancient

Father of geometry

Context

Proposition 4 (Side-Angle-Side Congruence), Book I of 'Elements'

Date / Period

c. 300 BCE

Source

https://en.wikibooks.org/wiki/Euclid%27s_Elements/Book_I

Verification

Unverifiable

Explanation

Found in 1 providers: grok

Method

Cross Reference

Sources Checked

1 source

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