Checking and securing understanding of congruence and similarity
I can identify (by eye) which shapes are congruent, similar or neither.
Checking and securing understanding of congruence and similarity
I can identify (by eye) which shapes are congruent, similar or neither.
These resources will be removed by end of Summer Term 2025.
Lesson details
Key learning points
- If two shapes are congruent, then they are similar.
- A ratio table can be a helpful tool for checking the multipliers.
- The multiplicative relationship between the sides of the object is preserved in its image.
- It can be easier to determine (by eye) which shapes are NOT congruent or similar.
Keywords
Similar - Two shapes are similar if the only difference between them is their size. Their side lengths are in the same proportions.
Congruent - If one shape can fit exactly on top of another using rotation, reflection or translation, then the shapes are congruent.
Object - The object is the starting figure, before a transformation has been applied.
Image - The image is the resulting figure, after a transformation has been applied.
Invariant - A property of a shape is invariant if that property has not changed after the shape is transformed.
Common misconception
Congruent shapes are not similar shapes.
Congruent shapes are similar shapes. The scale factor, or multiplier, between them is one.
To help you plan your year 10 maths lesson on: Checking and securing understanding of congruence and similarity, download all teaching resources for free and adapt to suit your pupils' needs...
To help you plan your year 10 maths lesson on: Checking and securing understanding of congruence and similarity, download all teaching resources for free and adapt to suit your pupils' needs.
The starter quiz will activate and check your pupils' prior knowledge, with versions available both with and without answers in PDF format.
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Starter quiz
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Exit quiz
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