Conditions for Congruence of Triangles

Develop the conditions for Congruence of Triangles (ACMMG201)

LO: To determine if two triangles are congruent.
Know:

  • The definition of congruence.

Understand:

  • That shapes that have the same properties are congruent.

Do:

  • I can use the congruency rules in order to determine whether two triangles are congruent or not.

Congruency

Congruent means a shape that is exactly equal in size and shape. Two triangles are congruent if one can be fitted exactly on top of the other. Sometimes you might need to ‘flip’ (reflect) or rotate the triangle in order to check to see if the triangle is congruent. 

Congruent angles mean that angles that have the same measure. These two angles are congruent.

Congruency Rules

In general, there are 4 congruency rules in order to determine whether two triangles are congruent or not.

SSS – Side, Side, Side Congruence Rule

ASA – Angle, Side, Angle Congruence Rule

RHS (Right-angled Triangles) – Right, Hypotenuse, Side Congruence Rule

SAS – Side, Angle, Side Congruence Rule

Interactives

Congruency Videos

Student Generated Videos

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