Question

Can someone help me with my geometry homework

Answer 1

sorry, wrong click! Anyway, medal for you :)

Answer 2

Premultiply by
\[\left[\begin{matrix}\cos(t) & -\sin(t) \\ \sin(t) & \cos(t)\end{matrix}\right]\]
For example, for 90 degrees, it would be:
\[\left[\begin{matrix}0 & -1 \\ 1 & 0\end{matrix}\right]\left[\begin{matrix}3 & 6 & 4 \\ 1 & 2 & 5\end{matrix}\right]\] =\[\left[\begin{matrix}-1 & -2 & -5\\ 3 & 6 & 4\end{matrix}\right]\](transpose)

Answer 3

you kinda over-complicated it a little bit but thanks anyway

Answer 4

Sorry about the complication, I should have noticed that the rotations are ll multiples of 90 degrees.

You probably learned the short version like
T-R90(x,y)=(-y,x)
and
T180(x,y)=(-x,y)
etc.

They all come to the above when the rotations are not multiples of 90 degrees.