Euclid index

Euclid Book 1 - Proposition 26
Congruent triangles if two sides and corresponding angle are equal

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To be proved: If two triangles have two angles equal to two angles respectively, and one side equal to one side, namely, either the side adjoining the equal angles, or that opposite one of the equal angles, then the remaining sides equal the remaining sides and the remaining angle equals the remaining angle.

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There are two triangles ABC and DEF where angles ABC = DEF and BCA = EFD, and line BC = EF


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