A farmer wishes to fence a rectangular area behind his barn. The barn forms one end of the rectangle and the length of the rectangle is three times the width. How many linear feet of the fence must he buy if the perimeter of the rectangle is 320 feet?

Respuesta :

Answer:

Therefore, he must buy [tex]280[/tex] feet of fence to form barn if the perimeter of the rectangle is [tex]320[/tex] feet.

Step-by-step explanation:

Considering '[tex]x[/tex]' be the width of the rectangle

  • As the barn forms one end of the rectangle and the length of the rectangle is three times the width.  

so

Length of the rectangle [tex]= 3x[/tex]

as

[tex]Perimeter\:of\:rectangle\:=\:2\left(l\times \:w\right)[/tex]

                                [tex]320 =2(x+ 3x)[/tex]

                      [tex]2\left(x+3x\right)=320[/tex]

                           [tex]\frac{2\left(x+3x\right)}{2}=\frac{320}{2}[/tex]

                                   [tex]4x=160[/tex]

                                     [tex]x=40[/tex]

Hence, the width of the rectangular area is [tex]40 feet[/tex] .

and

Length of the rectangle [tex]= 3x[/tex]

                                       = 3 × 40

                                       =120 feet

As it is clear that the barn makes one end of the rectangle.

[tex]\left(2\times \:l\right)+w[/tex]

[tex]=\left(2\times 120\right)+40[/tex]

[tex]=\left(2\times 120\right)+40[/tex]

[tex]=280[/tex]

Therefore, he must buy [tex]280[/tex] feet of fence to form barn if the perimeter of the rectangle is [tex]320[/tex] feet.

Answer:

280

Step-by-step explanation: