Question 1153541

let the dimensions of the field be {{{L}}} and {{{W}}}

if a rectangular field is {{{seven}}} times as long as it is wide, we have

{{{L=7W}}}.......eq.1


if the perimeter of the field is {{{P=800}}} feet,we have

{{{2(L+W)=800}}}

{{{L+W=400}}} ......eq.2, substitute {{{L}}} from eq.1


{{{7W+W=400}}} 

{{{8W=400}}} 

{{{W=400/8}}}

{{{W=50}}}

go to

{{{L=7W}}}.......eq.1, plug in {{{W}}}

{{{L=7*50}}}

{{{L=350}}}



answer: the dimensions of the field are {{{350}}} by {{{ 50}}}