What is the perimeter of a quadrilateral with vertices at (3,-6),(8,-6),(3,-4), and (8,-4)

Sum is 17 and their difference is 3

What is the approximate value of  x  in the equation below.–3.396–0.7080.3040.955

Adolphin is swimming with her friend. the dolphin jumps to a height of 4.54.54, point, 5 meters above the surface of the water as her friend swims 9.89.89, point, 8 meters directly below her. what is the position of the dolphin's friend relative to the surface of the water? meters