# Congruent and Similar Triangles | Summary and Q&A

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November 9, 2011
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Congruent and Similar Triangles

## TL;DR

Congruent triangles have the same size and shape, while similar triangles have the same shape but can be different in size.

## Questions & Answers

### Q: What is the difference between congruent and similar triangles?

Congruent triangles have the exact same size and shape, while similar triangles have the same shape but can be different in size.

### Q: How can you determine if two triangles are congruent?

Two triangles are congruent if all of their corresponding sides and angles are equal. This means that they have the same size and shape.

### Q: Can similar triangles have different side lengths?

Yes, similar triangles can have different side lengths. The key requirement for similarity is that their corresponding angles are equal or their corresponding side lengths have the same ratio.

### Q: How can you prove that two triangles are similar?

Two triangles can be proven to be similar if all of their corresponding angles are equal or if the ratio between their corresponding side lengths is the same.

## Summary & Key Takeaways

• Congruent triangles have the same side lengths and angles, while similar triangles have the same shape but can have different sizes.

• To be congruent, all corresponding sides and angles of two triangles must be equal.

• Similar triangles can have the same shape if their corresponding angles are equal or if the ratio of their corresponding side lengths is the same.