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Congruence of Triangles

In general we come across many figures having same shape and same size. Such objects are known as as congruent figures.  Two triangles are said to be congruent if all the sides and the angles of one triangle are respectively equal to corresponding sides and angles of other triangle.
Consider triangles ABC and DEF, If AB = DE, BC = EF, AC = DF and
then DABC @ DDEF. Two triangles can be said to be congruent by using any of these four rules. They are Side Angle Side(SAS) Rule, Angle Side Angle(ASA) Rule, Side Side Side(SSS) Rule, Right angle Hypotenuse Side(RHS) Rule.

SAS Congruence Rule: If two sides and included angle of one triangle are equal to the corresponding two sides and included angle of other triangle then the two triangles are congruent.

ASA Congruence Rule: If two angles and included side of one triangle are equal to the two angles and included side of other triangle then the two triangles are congruent.

SSS Congruence Rule: Three sides of one triangle are equal to three sides of other triangle then the two triangles are congruent.

RHS congruence rule: Two right triangles are said to be congruent if the hypotenuse and one side of one triangle are equal to the hypotenuse and corresponding side of the other triangle.