# Thread: Geometry... another sos...

1. ## Geometry... another sos...

Hi There;

Help.. help...

Find the 3x3 matrices that represent the following transformation of 2D space:

a) A rotation of -90 degrees about the origin followed by a translation of (3, -4)
b) A translations of (3, -4) followed by a rotaion of -90 about the origin
c) A rotation of -90 degrees abt the point (3, -4)
b) Find the image of A(1,2) under the transformation (a), (b) and (c) respectively.

Thank you.

2. Originally Posted by eureka
Hi There;

Help.. help...

Find the 3x3 matrices that represent the following transformation of 2D space:

a) A rotation of -90 degrees about the origin followed by a translation of (3, -4)
b) A translations of (3, -4) followed by a rotaion of -90 about the origin
c) A rotation of -90 degrees abt the point (3, -4)
b) Find the image of A(1,2) under the transformation (a), (b) and (c) respectively.

Thank you.
Are you sure you are asked to find 3x3 matrices to represent these transformations?

RonL

3. yes.. is 3x3...

4. Originally Posted by eureka
yes.. is 3x3...
In that case, what axes are the 90 degree rotations about?

-Dan