Enlargment

When using translation you always need to say:
How many times bigger you have made the shape (scale factor)
What the centre of enlargement is

The centre of enlargement is the point of which the shape started to enlarge (form)

The scale factor is how many times the shape is being enlarged.

The easy way to work out the scale factor of a shape on a grid is to first count how many squares are on one side of the smaller shape (preferably the bottom) you then count how many squares there are ON THE SAME SIDE on the enlarged shape. You then compare the two numbers and work out how many times the shape has been enlarged. (I like to use division)

Here, the first shape (pink) has 4 squares along the bottom side. In the enlarged shape the bottom side has 8 squares. I then use division to work out the scale factor.
8 divided by 4 gives 2. So 2 = the scale factor.








When working out the scale factor of a shape with no grid you use projection lines. Here is an example of what projection lines look like:

First you draw a projection line, starting from the middle of the X to one of the corners of the shape and beyond. You then measure that distance and double it. Then, starting from the X along the projection line you apply that doubled distance and then place a small mark at the end of the doubled distance. Repeat this for all of the corners. Your shape should now look like this:

Once you've done that you join up all of your new doubled distances to create a new and enlarged shape like so,

That is how you enlarge a shape without a grid. The tricky thing is though, even though you've enlarged the shapes all the angles are actually still the same!

Transformations: Translation

Translation is one of the 4 ways that a shape can be moved. (Translation, Rotation, Shrink and enlarge and reflect) If you have a shape on a grid and you then move the shape, you have translated it.

A vector is the coordinates of where the shape has been moved. A vector looks like the picture below.
The top number indicates how far left or right the shape has moved. If the number is negative the shape moves left, if the number is positive, the shape moves right. The bottom number indicates how far up or down the shape will move. If the number is negative the shape goes down and if the number is positive the shape goes up.









When moving house you are translating objects to the new house. This is a real life example of translation.

Rotating Shapes

1. What 3 things do you need to say to describe a rotation?

- Where the centre of rotation is

- How much it is turned through.

- Whether the rotation is clockwise or anticlockwise.

b. Explain what centre of rotation means

The centre of rotation is the coordinates that show where the shape will be turned from.

c. Now use these 3 things to describe the rotation on Page 1 of the myimaths lesson (i.e. describe the rotation of the triangle) The triangle The centre of rotation is 1,1. The triangle has been turned 90 degrees and is clockwise.

Rotational Symmetry

1. In your own words explain what rotational symmetry is.

Rotational symmetry is how many times a shape can be rotated and still look the same.

b.How is rotational symmetry different from line symmetry

Rotational symmetry is when the shape is moved to look the same but line symmetry is when a shape is exactly the same on either side and if you were to fold it in half, both sides would be exactly the same.

c. What do you do to check if a shape has rotational symmetry?

By rotating a shape and seeing if it looks the same when in a different position.

d. Find pictures of 3 real life objects which have rotational symmetry (not shapes, objects e.g. foods, logos) and paste them into your post

1.

2.

3.

Mean, Median and Mode Song

Lyrics

Mode, Median, Mean and Range
Mode, Median, Mean and Range

Don't you think these words sound strange?
Don't you think these words sound strange?

I will get your mind to change


Mode, Mode, Mu, Mu, Mu, Mode, Mode
Is the number that occurs occurs the most most
Singing Mode, Mode, Mu, Mu, Mu, Mode, Mode
Is the number that occurs occurs the most most
You got 1,2,2,3,3,3,4
1,2,2,3,3,3,4, which of those numbers did I say more?
which of those numbers did I say more? 3 is the mode cause it occurs the most
Mode, Mode, Mu, Mu, Mu, Mode, Mode
Is the number that occurs occurs the most most
Singing Mode, Mode, Mu, Mu, Mu, Mode, Mode
Is the number that occurs occurs the most most
You got 1,2,2,3,3,3,4
1,2,2,3,3,3,4, which of those numbers did I say more?
which of those numbers did I say more? 3 is the mode cause it occurs the most
Now stop, lets take it to the middle. Got to find the median no time to daddle diddle
Line up all the numbers from the smallest to the big and the ones thats in the middle does a media jig
Go median, middle number, go median, middle number
Now the third ones mean, not nice but mean
Its the average number if you know what I mean
Just add up all the numbers and divide them by the number of added
Whats that, whats mean?
You add up all the numbers and divide them by the number of added
Yeah you know what I mean
You add up all the numbers and divide them by the number of added
It's the average number, mean, its the average number
1 more round and the song is done
Lets talk about range and have some fun
It's the biggest number minus the smallest number, in the group, in the group
It's the biggest number minus the smallest number , in the group, in the group

You got Mode, Median, Mean and Range
Mode, Median, Mean and Range

Don't you think these words sound strange?
Don't you think these words sound strange?

I just got your mind to change

Quick Explanation

Mean: The mean is the average number. Add up all the numbers and divide them by the number of added.
Median: You line up the numbers from smallest to big and the median is the number in the middle.
Mode: The mode is the number that occurs the most.
Range: The range is the biggest number minus the smallest number in the group

number

Examples
Mean:
If my numbers are 3,2,3,4, the mean is 3 because I add all the numbers = 12 then I divide by 4 because there are 3 numbers.
Median:
If my numbers are 1,2,3,4,5 the median is 3 because it is the middle number.
Mode:
If my numbers are 1,2,2,3,3,3,4 the mean is 3 because it occurs the most.
Range:
If my number are 8,2,4,3 the range is 6 because I get my largest number, 8 and minus the smallest number, 2 which equals 2.