12a + 12b + 12c + 12d michael writes the expression shown here as 12(a + b + c + d). he is correctly using the property. a) associative b) commutative c) distributive d) symmetric

If 3x+8=3x+8 is it one solution or no solution

You are at a restaurant and owe $38 for your meal. you want to leave a 20% tip. how much will your tip be?

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.