##l=120yds##

##w=53yds##

A football field resembles as a rectangle.

The perimeter of a rectangle can be determined by the equation:

##P=2l+2w rarr## equation 1

where:

##P rArr##perimeter

##l rArr##length

##w rArr## width

Converting the given to an algebraic expression gives us:

##color(red)l=14yds+2w rarr##equation 2

Using this expression we can replace ##color(red)l## from equation 1 and come up with a formula that would determine the value of the width.

From equation 1 we have:

##P=2color(red)l+2w##

##P=2(color(red)(14yds+2w))+2w##

##rarr##simplifing the equation gives us

##color(blue)P=28yds+6w##

then

##color(blue)(346yds)=28yds+6w##

##6w=346yds-28yds##

##6w=318yds##

##w=(318yds)/6##

##w=53yds##

Then to find the length simply substitute the value of the width to the equation 2.

##l=14yds+2w##

##l=14yds+2(53yds)##

##l=120yds##

##:.## the dimension of the field is ##120yds## by ##53yds##