Rotating Shapes

This chapter explores rotating shapes. Itcovers rotating shapes around a coordinat grid, and describing rotations using angles and centres of rotations.

Introduction

We shall look at transforming shapes around a grid using rotation. Below is a shape on a grid that we could use for this practice.

To describe a rotation we need to identify the centre of rotation, how much it is turned for example angle such as 90 degrees, and whether the rotation is clockwise or anticlockwise

Describing rotations

Here we shall explore describing rotations. Below is a grid with shpe E rotated on to shape F.

We can see that the angle of rotation is 90 degrees clockwise. The centre of rotation is at;

Direction of rotation

We describe an anticlock wise rotation as a positive rotation. The diagram below shows a positive rotation of 90° about 10.

You can describe the rotation as a rotation of +90° about O.
We call a clockwise rotation a negatve rotation. The diagram below shows a negative rotation of 90° about O.

You could describe the rotation above +90 about O.