Please provide explaination.

The vertices of a rectangle are given in the columns of the matrix . if is found to perform a transformation, what are the coordinates of the transformed rectangle? (0, 0), (0, –3), (–3, –3), (–3, 0) (0, 0), (0, 3), (3, 3), (3, 0) (0, 0), (0, 3), (–3, –3), (–3, 0) (0, 0), (0, 3), (–3, 3), (–3, 0)

How do you use the elimination method for this question? explain, because i really want to understand!

Aline passes through the point (–7, 5) and has a slope of 1/2 which is another point that the line passes through?