Answer:
(1)
And for this case we know the following condition "The length of the field is 7 yards less than quadruple the width" and we can write this :

And replacing into equation (1) we got:



Adding 14 in both sides we got:

And dividing 10 on both sides we got:

And then we can solve for X and we got:

Explanation:
For this case we can set up the following notation:
X represent the lenght
Y represent the width
And since we have a rectangular playing filed the perimeter is given by:
(1)
And for this case we know the following condition "The length of the field is 7 yards less than quadruple the width" and we can write this :

And replacing into equation (1) we got:



Adding 14 in both sides we got:

And dividing 10 on both sides we got:

And then we can solve for X and we got:
