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### History and Feedback

#### Checkpoint description

Describe what's changed since the last checkpoint.

#### Christian Lawson-Perfect2 years, 1 month ago

Gave some feedback: Ready to use

#### Christian Lawson-Perfect2 years, 1 month ago

Saved a checkpoint:

Not massively happy with this - the centre of enlargement is always $(0,0)$ and the scale factor is always $\pm 2$.

The diagrams aren't very precisely drawn either.

I've reworded the advice so it actually gives the answers.

Published this.

#### Aiden McCall2 years, 2 months ago

I have changed the one where it reflects in $y = -x$  so that there is a letter at each vertex. It is the only question that does it though so seems out of place. If it does seem too out of place it can be removed easily.

#### Aiden McCall2 years, 2 months ago

Gave some feedback: Needs to be tested

#### Chris Graham2 years, 2 months ago

Gave some feedback: Has some problems

#### Chris Graham2 years, 2 months ago

The diagram with rectangles of the same scale reflected across $y=-x$ are very confusing. To start with, I would avoid having the same, albeit negative, scale. Your question statement says "Describe the transformation of image A to B." From that statement, describing this transformation in terms of enlargement is a strange thing to do (rotation or reflection come to mind).

In the advice, to the naive student, the way that you describe finding the centre of enlargement - drawing lines between corresponding vertices (e.g. top left of A And top left of B) - the lines do not intersect at all.

I guess the point is that it is not clear from your diagram that B has inverted (this is only clear when you reverse engineer it, starting with the first image and applying the scale factor to each vertex). You would need to label the individual vertices on both A and B to make that clear, or just avoid this example altogether.

#### Aiden McCall2 years, 2 months ago

Gave some feedback: Needs to be tested

#### Aiden McCall2 years, 2 months ago

Gave some feedback: Has some problems

#### Aiden McCall2 years, 2 months ago

Created this.

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