Transformations for OCR GCSE Maths
This page covers the following topics:
Rotation is a transformation which rotates a shape around a point in a certain direction at a certain angle. This point is the centre of rotation. To describe a rotation, the direction, the angle and the centre of rotation must be stated.
A reflection is when a shape is reflected across a line to create an image. This line is called the line of reflection. Every point in the shape will be the same distant away from the line of reflection as the image. The line that joins the original point in the shape with the same point in the image is perpendicular to the line of reflection.
A translation is a transformation that moves a shape around a grid without altering its appearance. Every point in the shape is translated a certain given distance and direction.
An enlargement is a transformation that changes the size of a shape. For an enlargement to be described, a scale factor and a centre of enlargement are needed. In an enlargement, the distance from the centre of enlargement to the points on the shape are multiplied by a scale factor. When the scale factor is negative, the enlargement will be produced on the opposite side of the centre of enlargement to the original shape.
Draw a unit square with its left bottom corner at (3, 1). Reflect the square in the x-axis.
Describe the reflection in the given diagram.
This is a reflection in the x = 4 line.
Sketch a triangle of coordinates (1,1), (5, 1) and (5, 5). On the same grid, rotate the triangle by 90º clockwise about (3, 2).
Describe the transformation in the given diagram.
The transformation is an enlargement of scale factor 1/2 with the origin as the centre of enlargement.
Draw a square with coordinates (1, 3), (1, 5), (3, 3) and (3, 5). Translate the square 2 units down and 2 units right.
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