The preimage WXYZ is to undergo a rotation of 90° in the clockwise direction. A 90° clockwise rotation leads to the following change in the coordinates; (x,y) -> after rotation (y,-x) this rule applies for all the vertices in the preimage W - (3,-5) --> W' (-5,-3) X - (1,-3) ---> X' (-3,-1) Y - (-1,-5)---> Y' (-5,1) Z - (1,-7) ---> Z' (-7,-1) therefore the new coordinates are W' (-5,-3), X' (-3,-1), Y' (-5,1) and Z' (-7,-1)
18 is the old value and 12 is the new value. In this case we have a negative change (decrease) of -33.33333333 percent because the new value is smaller than the old value.
