Anew outdoor recreation center is being built in madison. the perimeter of the rectangle playing field is 382 yards. the length of the field is 9 yards less than quadruple the width. what are the dimensions of the playing field

Width= x
length=4x-9

perimeter of a rectangle is the sum of all sides:

Perimeter=2(width)+2 length

In this case: 

Perimeter = 382 yd;
then:

2(x)+2(4x-9)=382
2x+8x-18=382
10x=382+18
10x=400
x=400/10=40     (with=40 yd)

(4x-9)=4(40)-9=160-9=151    (length=151 yd)

the dimensions of the playing field are width=40 yd and length=151 yd.

Idon't know the answer