Question

what is congruency of a triangle ?
please teach me from the basics because i have no idea what it is

Answer 1

Two triangles are said to be in CONGRUENT,if their length of their
corresponding  Sides are equal and their corresponding angles are equal
Tests for congruency between two triangles are:-  
1.SIDE-SIDE-SIDE
2.SIDE-ANGLE-SIDE
3.SIDE-SIDE-ANGLE
4.ANGLE-SIDE-SIDE
5.ANGLE-SIDE-ANGLE
6.ANGLE-ANGLE-SIDE
For Right angled triangles,Right angle-Hypotenuse-side.