Question

A farmer wants to build a rectangular pen using 20 feet of fencing, but the length is to be 4 feet more than the width. What is the length of the pen, in feet?

Answer 1

7ft

Explanation:

2W+2L=20

2(W+L)=20

2(W+(W+4))=20

4W+8=20

4W=12

W=3

or

If 20 is the total length of fencing used, the length of the fence is to be 4 ft longer than the width, and we know this is a rectangular pen (meaning it has 4 sides), we first multiply 4 (the additional ft for the length side) by two to get 8. Next we subtract 8 from the total amount of fencing (20) to get 12. Finally, since we know there are 4 sides to a rectangle, we divide 12 by 4 to get the width. Now since the length is 4 ft longer than the width, and we are looking for the length, then we add 3+4 to equal 7.

7 is the length.

Answer 2

The length of the rectangular pen is 40ft. The width of the rectangular pen is 20ft