Find all the missing measurement​

One side of a rectangle is 7 feet shorter than seven times the other side. find the length of the shorter side if we also know that the perimeter of the rectangle is 306 feet.

10 ! in a race, nick is 50 feet in front of jay after ten seconds. how fast can nick run, if jay can run 20 feet per second?

What are the solutions of the system? solve by graphing. y = -x^2 - 3x + 2 y = -2x + 2