Congruence in shapes | Maths | Quizalize & Oak National Academy

Starter quiz

Which transformations always produce an image that is congruent to the object?
- enlargement
- reflection ✓
- rotation ✓
- translation ✓
When two shapes are congruent, which property of the shapes always remain invariant?
- angles ✓
- lengths ✓
- orientation
- position
The table shows the base and height of four rectangles. Which rectangle is congruent to a rectangle that is 6 cm by 3 cm?
- A
- B ✓
- C
- D
Which triangle is congruent to triangle T?
- A
- B ✓
- C
- D
- E
Angles in a quadrilateral sum to ______°.
- '360' ✓
The diagram shows a pair of angles on parallel lines. When $x=145$ , $y=$ ______.
- '35' ✓

Exit quiz

Triangles A and B are congruent. Match each unknown length from triangle B with its size.
- $a\text{ cm}$
  
  ⇔
  
  4 cm ✓
- $b\text{ cm}$
  
  ⇔
  
  6 cm ✓
- $c\text{ cm}$
  
  ⇔
  
  5 cm ✓
Triangles A and B are congruent. Match each unknown angle from triangle B with its size.
- $a°$
  
  ⇔
  
  44° ✓
- $b°$
  
  ⇔
  
  79° ✓
- $c°$
  
  ⇔
  
  57° ✓
The image shows two congruent hexagons. What is the size of the angle $x°$ ?
- 110°
- 112°
- 146° ✓
The image shows two congruent pentagons. What is the value of $x$ ?
- 43
- 50 ✓
- 59
Shape T is a trapezium. Which quadrilateral contains enough information to determine whether it is congruent to shape T?
- A
- B ✓
- C
Shape R is a rhombus. Which quadrilateral is not congruent to shape R?
- A
- B
- C ✓

Worksheet

Loading worksheet ...

Presentation

Loading presentation ...

Lesson Details

Key learning points

Two shapes are not congruent if there is a pair of lengths with a scalar not equal to one.
Congruent does not mean the orientation must be the same.
The angle sizes do not change.

Common misconception

Pupils may think that they do not have enough information about a shape to determine whether it is congruent to another shape, when in fact they do.

Pupils could attempt the draw the shape based on the information that they have. They can then consider whether there are multiple way that the shape can be drawn while still satisfying all the given information.

Keywords

Congruent - If one shape can fit exactly on top of another using rotation, reflection or translation, then the shapes are congruent.
Co-interior angles - Co-interior angles are on the same side of the transversal line and in between the two other lines.