Need help with math problem if do get 5 star

Asequence is defined recursively using the formula f(n + 1) =f(n) - 5. which sequence could be

The numbers on a football field indicate 10 yard increments. you walk around the perimeter of a football field between the pylons. you walk a distance of 30623 yards. find the area and perimeter of the indicated regions. write your answers as mixed numbers, if necessary. a. one end zone: perimeter: yd area: yd2 b. the playing field (not including end zones): perimeter: yd area: yd2 c. the playing field (including end zones): perimeter: yd area: yd2

Solve for x: 5/3 x = 20/21 it's fraction. remember to simplify your fraction