Find the value of y in the rhombus below

Which expresions are equivalent to the one below? check all that apply. 5x

Which of these choices show a pair of equivalent expressions?

Set $r$ is a set of rectangles such that (1) only the grid points shown here are used as vertices, (2) all sides are vertical or horizontal and (3) no two rectangles in the set are congruent. if $r$ contains the maximum possible number of rectangles given these conditions, what fraction of the rectangles in set $r$ are squares? express your answer as a common fraction.