Question 989348


A building in a city has a {{{rectangular}}} base. 

if the length {{{L}}} of the base measures {{{70ft}}} less than three times the width {{{W}}}, we have 

 {{{L=3W-70ft}}}

if the perimeter {{{P=2(L+W)}}} of the base is {{{900ft}}}, than

{{{2(L+W)=900ft}}}.....substitute {{{3W-70ft}}} for {{{L}}}

{{{2(3W-70ft+W)=900ft}}}...........solve for {{{W}}}

{{{2(4W-70ft)=900ft}}}

{{{8W-140ft=900ft}}}

{{{8W=900ft+140ft}}}

{{{8W=1040ft}}}

{{{W=1040ft/8}}}

{{{highlight(W=130ft)}}}

now find {{{L}}}:

 {{{L=3W-70ft}}}

 {{{L=3*130ft-70ft}}}

 {{{L=390ft-70ft}}}

{{{highlight(L=320ft)}}}


so, the dimensions of the base are:{{{highlight(L=320ft)}}}, {{{highlight(W=130ft)}}}