Please help me solve this

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.

When is g(x) = 0 for the function g(x) = 5.23x + 4?

Felix wrote several equations and determined that only one of the equations has no solution. which of these equations has no solution?