What is rotation?
Rotation in Maths is where you take a shape and turn it.
What do I need to rotate an object?
If you tried to describe something that was turning in real life, you would need to give three pieces of information.
Which way it was turning, how far it turned and what it was turning around.
In Maths, these would be called...
1) Distance - How many degrees the object was turned. At GCSE maths, this is normally limited to 90°,180° and 270°,
2) Direction - This is referred to in Maths by clockwise (CW) and anticlockwise (ACW)
3) The Centre of Rotation - In any rotation, there is a point that doesn't move. We define this point as a coordinate.
How to rotate an object.
There are a couple of pieces of equipment you need here. Firstly a pencil (sharpened) and secondly some tracing paper (Greaseproof kitchen paper works just as well)
Example 1: Rotate this triangle 90° clockwise around the point (1,1)
Step 1: Draw out what information you are given
Sometimes, the shape will be drawn for you, but if not, draw the shape AND the centre of rotation.
Step 2: Trace
Put your tracing paper over your shape, making sure you cover the centre of rotation.
I would recommend that when you trace the centre, draw a cross over the centre, this makes it easy to see if you have rotated exactly 90°.
Step 3: Complete the rotation
Place the point of your pencil on the centre of rotation (this makes sure it doesn't move while you turn the tracing paper) and turn the tracing paper 90° clockwise.
Step 4: Transfer the image and label
The easiest way to transfer the shape back onto the paper is to press on the corners of the shape with your pencil (do this lightly)
This will give three little dips in the paper underneath that you can just join up to finish the shape.
Remember that if the image is labeled a, the rotation will be labeled a'