Lesson video

Hi, I'm Ms. Davies and in this lesson we're going to be translating and describing translations using a 2D vector.

A vector is a description of both direction and magnitude of a movement.

It tells you how many units to move and in which direction.

The instruction five right, three up, can be written as the vector five three.

The top value gives you the x component, this is how many squares it moves in a horizontal direction.

The bottom value is the y component, it tells you how many units to move in a vertical direction.

The instruction six left, seven up, can be written as the vector negative six seven.

The top value, which is the horizontal component, is a negative value if it is a movement left and it's a positive value if it is a movement right.

The bottom value, which is the vertical component, is a positive value for any upward movement and a negative value for downward movements.

The instruction four down is written as the vector zero negative four.

It doesn't have a horizontal component so the top value is zero.

As it is a movement down the second value is negative.

The instruction eight left is written as the vector negative eight zero as it is a movement to the left the top horizontal component is a negative value and as there is no vertical movement the bottom value is zero.

We have been asked to translate shape C by the vector negative two four to give shape D.

We're going to move shape C two units to the left and four units up.

This is the movement of two squares left, and this is the movement of four squares up.

This is the position of shape D.

Here are some questions for you to try.

Pause the video to complete your task and resume once you're finished Here are the answers.

The vector two one means moving two squares to the right and one square up.

When you're doing the translations make sure that the dimensions of the shapes are the same.

Shape A has been translated to give shape B.

What is the vector it has been translated by? We need to work out the number of units shape A has been moved to be in the position of shape B.

I'm going to work with the top right vertex in both of the shapes.

You can see that the top right vertex moves three squares to the right, and then four squares down.

This gives the vector three negative four.

Here are some questions for you to try.

Pause the video to complete your task and resume once you're finished.

Here are the answers.

Remember that the top value is movement in the x direction, positive moves right, negative moves left, and the second value is moving in the y direction where positive is up, and negative is down.

Here are some questions for you to try.

Pause the video to complete your task and resume once you're finished.

Here are the answers.

Make sure that you're comparing the same point on both of the shapes.

Here are some questions for you to try.

Pause the video to complete your task and resume once you're finished.

Here are the answers.

Mark has moved five squares to the right instead of four.

That's all for this lesson.

Thanks for watching.