Congruent Shapes
Two shapes are congruent if they have exactly the same shape and size. Congruent shapes can be rotated, reflected, or translated, but their side lengths and angles remain equal.
What You Need to Know
Key Concept Diagram
Congruent figures have identical shape and size — all corresponding sides and angles are equal
Transformations (rotations, reflections, translations) produce congruent images
Congruent triangles can be proven using SSS, SAS, AAS, or RHS conditions
The symbol for congruence is the congruence sign (≅)
Key Vocabulary
Congruent
Having exactly the same shape and size
Corresponding
Matching sides or angles in two congruent or similar figures
Transformation
A movement of a shape: translation, rotation, or reflection
SSS
Side-Side-Side: a condition for proving two triangles are congruent
Knowledge Check
Select the correct answer for each question. Click "Check Answer" to see if you are right.
Question 1
Two triangles have sides of 3 cm, 4 cm, and 5 cm each. Are they congruent?
Question 2
Which transformation does NOT produce a congruent image?
Question 3
What is the symbol for congruence?
Key Concepts Summary
- ●Congruent figures have identical shape and size — all corresponding sides and angles are equal
- ●Transformations (rotations, reflections, translations) produce congruent images
- ●Congruent triangles can be proven using SSS, SAS, AAS, or RHS conditions
- ●The symbol for congruence is the congruence sign (≅)