The length of a rectangle is
2
meters more than
2
times the width. If the area is
40
square meters, find the width and the length.

Respuesta :

corm

Answer:

Step-by-step explanation:

From the problem statement, we can set up the following two equations:

[tex]L = 2W + 2[/tex]

[tex]40 = L * W[/tex]

Plugging the first equation into the second, we can solve for [tex]W[/tex]:

[tex]40 = L * W[/tex]

[tex]40 = (2W + 2) * W[/tex]

[tex]40 = 2W^{2} + 2W[/tex]

[tex]2W^{2} + 2W - 40 = 0[/tex]

[tex]W^{2} + W - 20 = 0[/tex]

[tex](W + 5)(W - 4) = 0[/tex]

[tex]W = -5, 4[/tex]

Since the length must be a positive number, then we know that [tex]W = 4[/tex]. We can now plug this number into the second equation to get [tex]L[/tex]:

[tex]40 = L * W[/tex]

[tex]40 = L * (4)[/tex]

[tex]L = 10[/tex]

Answer:

Step 1

Let length and breadth be x and y respectively

Given

x=2+2y

Step 2

Area of rectangle is lengthxbreadth

Therefore

area=x times y

Area=(2+2y)*y

=2y+2y^2

Area=40

Step 3

40=2y+2y^2

2y^2+2y-40=0

The roots are - 8 and 10

The equation is:

2y^2+10y-8y-40=0

2y(y+5)-8(y+5)=0

Which gives

y=-5 and y=4

Y=5 Rejected,

Therefore

y=4,breadth=4

So length=10(2*4+2)

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