Word Problem

Question

Jackie and Ken are building a fence around a rectangular field. They want to enclose an area of 75 square feet. The width should be 3 feet longer than the length of the field. What are the dimensions of the field? Round to the nearest tenth, if necessary.

Answer 1

Area of a rectangular field = Length* width =75 sq ft

Suppose length= x ft, Width =x+3 ft

75 =x(x+3)

75=x² +3x

x² +3x-75=0

 

x= -b±√b² -4ac  /2a

   = -3±√9+300/2

  =-3±√309  /2=-3±17.58/2

7.25   or 10.29

length = 7.3 ft            or      length = 10.3 ft

width = 10.3 ft                    width= 13.3 ft     .... not possible when you check your answer

Ans: Length=7.3 ft, width =10.3ft