The temperature started at 35 f. if the temperature went down 4°f and then up 2 f, whats is the temperature differe relative to the high temporature?

How to solve a simultaneous equation involved with fractions?

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.

Tell whether the two rates form a proportion