In the school band, 5/8 of the students play a brass instrument. Only 1/5 of the students who play a brass instrument play the trumpet. What fraction of the band students play the trumpet?

Can someone explain the elimination method to me for this problem?

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)

What is the best way to answer questions with a x expression in the question. for example 3x + 10x=?