Use the distance formula to find the lengths of the
sides of the second triangle, triangle PQR.

Choose all answers that apply: a) ab and a’b’ are one the same line. b) quadrilaterals abcd and a’ b’ c’ d’ have the same perimeters. c) points a and a’ have the same coordinates. d) none of the above

What is the greatest number of parts of a circle that can be formed by cutting the circle with 7 straight cuts? (note: the parts do not have to be equal in size)

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.