Enlargement

This refers to shapes that are the same except for their size.

The diagram below shows enlargement.

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It is important when describing enlargements, to say how much the shape has been enlarged by. We use ‘scale factor’ to do so. For example, if the side-lengths of the original shape enlarged three times then the scale factor is 3.

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The centre of enlargement is the position of the enlarged shape.

To draw an enlarged shape:

  • Draw lines from the centre of enlargement, through each point of the shape
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  • Depending on the scale factor, multiply the lengths of the sides by the scale factor.
  • Draw the enlarged shape.
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