# Congruence of Triangles

Chapter

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## Abstract

This chapter is devoted to the study of the usual sets of necessary and sufficient conditions for two triangles to be considered *the same*, in a sense it will soon be made precise. We also discuss here the important *fifth axiom* of Euclid (known as the axiom of parallels), as well as several interesting and important consequences of it, most notably the triangle inequality. Finally, in the last section of the chapter, several special types of quadrilaterals will make their first appearance.

## References

- 11.T.L. Heath,
*The Thirteen Books of Euclid’s Elements*(Dover, Mineola, 1956)Google Scholar - 19.E.E. Moise,
*Elementary Geometry from an Advanced Standpoint*(Addison-Wesley, Boston, 1963)Google Scholar - 24.I.M. Yaglom,
*Geometric Transformations I*(MAA, Washington, 1962)Google Scholar

## Copyright information

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