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If two shapes are **congruent**, they are
**identical** in both **shape and size**.

**Remember: ** Shapes can be congruent even if one of
them has been rotated or reflected.

- Question
Which of the shapes in the illustration above are congruent?

- Answer
Did you get the following pairs?

**A**and**G****D**and**I****E**and**J****C**and**H**

**Remember:**Shapes can be congruent even if one of them has been rotated (as in**A**and**G**) or reflected (as in**C**and**H**).

The symbol means 'is congruent to'.

Two triangles are congruent if **one** of the following conditions applies:

The three sides of the first triangle are equal to the three sides of the second triangle (the SSS rule: **S**ide **S**ide **S**ide).

Two sides of the first triangle are equal to two sides of the second triangle, and the **included** angle is equal (the SAS rule: **S**ide **A**ngle **S**ide).

Two angles in the first triangle are equal to two angles in the second triangle, and one (similarly located) side is equal (the AAS rule: **A**ngle **A**ngle **S**ide).

In a right-angled triangle, the hypotenuse and one other side in the first triangle are equal to the hypotenuse and corresponding side in the second triangle (the RHS rule: **R**ight-angled, **H**ypotenuse, **S**ide).

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