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Congruency 1

Congruency 1

Congruency 1

Shapes are congruent if they are exactly alike, and there are rules which govern how shapes can be congruent.

Two shapes are congruent if they are exactly the same shape. If you place one shape on top of the other and they completely overlap, then they are congruent shapes.

Congruent shapes are different from shapes that are mathematically similar. In congruent shapes, both the corresponding angles and sides are the same.

We can use certain rules to prove that two shapes are congruent.

Right angled triangles have another rule by which we can find out if they are congruent.

To prove that two triangles are congruent, we always need specific information. Think of these like 4 bullet points.


State the condition of congruency you are using.

The first bullet point should simply state the criteria you have used: e.g. SSA/ASA/AAS


Prove each criteria individually, justifying each point.

For the remaining 3 bullet points you should write how you know that the required angle or side is the same in both triangles.