Question 927341
Perimeter  =30 feet
Let width be w 
length  = 4 times the width
        = 4*w
        = 4w
But perimeter =  2(length+width)
        30 = 2(4w+w)
       30 = 2(5w)
          30 = 10 w
divide with 10 on both sides
 {{{ 30/10  = 10w/10}}}
        3 =w
so width = 3 feet
length  = 4*3  = 12 feet
Result: Width = 3 feet  & length  = 12 feet