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**Shear N first**

Here shear *N* (with a slanting invariant line through D) is applied to square ABCD.

What shape and size is the resulting image?

How far have points A, B and C moved?

What are their distances from the invariant line *n*?

What is the shear factor of shear *N*?

On the next page we apply a shear *P* to the image, which produces the same size rectangle as *M*-then-*N*.

What can you say about the invariant line for *P*, and what is the shear factor?