Transformations - AQAThe equation of the line of symmetry

Transformations change the size or position of shapes. Congruent shapes are identical, but may be reflected, rotated or translated. Scale factors can increase or decrease the size of a shape.

Part ofMathsGeometry and measure

The equation of the line of symmetry

Click to explore updated revision resources for GCSE Maths: Reflection, with step-by-step slideshows, quizzes, practice exam questions, and more!

To describe a reflection on a grid, the equation of the mirror line is needed.

Example

Reflect the shape in the line \(x = -1\).

Triangle ABC on a set of co-ordinates

The line \(x = -1\) is a vertical line which passes through -1 on the \(x\)-axis.

Triangle (ABC) reflected in the line, x=-1

Question

Describe the transformation of the shape ABC.

Triangle (ABC) reflected in the line, y=1

Question

Reflect the shape in the line \(y = x\).

Triangle ABC on a set of co-ordinates

Question

Describe the transformation of the shape ABC.

Triangle (ABC) reflected in the line, y=-x

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