the area of a rectangular wall of a barn is 36 square feet. Its length is 6 feet longer than twice its width. Find the length and width of the wall of the barn.
(6+2w)*w=36
6w+2w^2=36
2w^2+6w-36=0
2(w^2+3w-18)=0
2(w+6)(w-3)=0
w=3 or w=-6
width cannot be negative thus it must be 3
if the width is 3 then
36=3l
36/3=l
12=l
Hope this helps
Answer:
The length is 12 feet and width is 3 feet of the wall of the barn.
Step-by-step explanation:
Given : The area of a rectangular wall of a barn is 36 square feet. Its length is 6 feet longer than twice its width.
To Find : The length and width of the wall of the barn ?
Solution :
Let the width of the wall is 'w'.
Its length is 6 feet longer than twice its width.
The length of the wall is l=6+2w
The area of the wall is 36 square feet.
The area of the rectangular wall is \(A=l\times w\)
\(36=(6+2w)\times w\)
\(36=6w+2w^2\)
\(w^2+3w-18=0\)
Apply middle term split,
\(w^2+6w-3w-18=0\)
\(w(w+6)-3(w+6)=0\)
\((w+6)(w-3)=0\)
\(w=-6,3\)
Reject w=-6
The width of the wall is w=3 feet.
The length of the wall is l=6+2(3)=6+6=12
Therefore, The length is 12 feet and width is 3 feet of the wall of the barn.