The perimeter of a rectangle is 56 feet. Describe the the possible lengths of a side if the area of the rectangle is not to exceed 132 square ft

Respuesta :

P = 2(L + W)
56 = 2(L + W)
56/2 = L + W
28 = L + W.....L = 28 - W

A = L * W
132 =  W(28 - W)
132 = -W^2 + 28W
W^2 - 28W + 132 = 0
(W - 6)(W - 22) = 0

W - 6 = 0             L = 28 - W
W = 6                  L = 28 - 6
                            L = 22

W - 22 = 0           L = 28 - W
W = 22                L = 28 - 22
                           L = 6

not sure which (length or width)....one of them is 6 ft and the other is 22 ft

The possible lengths of sides of the rectangle will be  [tex](6,22)[/tex] or [tex](22,6)[/tex] .

What is area ?

Area is the space which is occupied by any [tex]2D[/tex] surface.

Area of rectangle [tex]=Length\ *\ Breadth[/tex]

Perimeter of rectangle [tex]=2(Length\ +\ Breadth)[/tex]

We have,

Perimeter of rectangle [tex]=56[/tex] feet

Area of rectangle  [tex]=132[/tex] squared feet

Let,

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

Breadth of rectangle [tex]=y[/tex]

So,

Perimeter of rectangle [tex]=2(Length\ +\ Breadth)[/tex]

                                   [tex]56=2(x+y)[/tex]

                                  [tex]28=(x+y)[/tex]

⇒                                 [tex]x=28-y[/tex]     [tex]........(i)[/tex]

Now,

Area of rectangle [tex]=Length\ *\ Breadth[/tex]

                        [tex]132=x\ *\ y[/tex]           [tex]........(ii)[/tex]

Now substitute value of [tex]x[/tex] in [tex](ii)[/tex],

[tex]132=(28-y)y[/tex]

[tex]132=28y-y^2[/tex]

⇒[tex]y^2-28y+132=0[/tex]

Now using Middle term split method;

[tex]y^2-28y+132=0[/tex]

[tex]y^2-22y-6y+132=0[/tex]

[tex]y(y-22)-6(y-22)=0[/tex]

[tex](y-6)(y-22)=0[/tex]

[tex](y-6)=0[/tex]

⇒  [tex]y=6[/tex]

[tex](y-22)=0[/tex]

⇒  [tex]y=22[/tex]

So,

Now if we take [tex]y=6[/tex], then

[tex]x=28-6[/tex]

[tex]x=22[/tex]

And,

if we take [tex]y=22[/tex], then

[tex]x=28-22[/tex]

[tex]x=6[/tex]

So, the possible lengths of sides of the rectangle are [tex](6,22)[/tex] or [tex](22,6)[/tex] .

Hence, we can say that he possible lengths of sides of the rectangle are  [tex](6,22)[/tex] or [tex](22,6)[/tex] .

To know more about rectangle click here

https://brainly.com/question/20693059

#SPJ3

Otras preguntas