Respuesta :
Answer:
See below.
Step-by-step explanation:
Here it is given that a school is building a field whose length is 40 yards more than its breadth. So if we assume the breadth to be x then its length will be x +40 .
[tex]\begin{picture}(10,6)\setlength{\unitlength}{1cm}\thicklines\put(0,0){\line(1,0){5}}\put(5,0){\line(0,1){3}}\put(5,3){\line(-1,0){5}}\put(0,3){\line(0,-1){3}}\put(2.5,-0.5){$\sf x +40$}\put(5.3,1.5){$\sf x $}\put(1,1){$\bf Area = 6000\ yard^2$}\end{picture}[/tex]
Now we know that the area of rectangle is ,
[tex]\longrightarrow Area = length\times breadth [/tex]
Substitute,
[tex]\longrightarrow x( x +40)= 6000 \\[/tex]
[tex]\longrightarrow x^2+40x = 6000\\[/tex]
[tex]\longrightarrow x^2+40x -6000=0\\ [/tex]
[tex]\longrightarrow x^2+100x -60x -6000=0\\ [/tex]
[tex]\longrightarrow x(x+100)-60(x+100)=0\\ [/tex]
[tex]\longrightarrow (x+100)(x-60)=0\\ [/tex]
[tex]\longrightarrow \underline{\underline{ x = 60 , -100}}[/tex]
As sides can't be negative, therefore,
[tex]\longrightarrow x = 60 [/tex]
Therefore,
- [tex]\longrightarrow Length = x+40 = 100\ yards [/tex]
- [tex]\longrightarrow Breadth = x = 60\ yards[/tex]
By solving a quadratic equation we will see that the width is 60yd and the length is 100yd.
How do find the dimensions of the soccer field?
Remember that for a rectangle of length L and width W, the area is:
A = L*W
In this case, we know that the length is 40 yards larger than the width, then we have:
L = W + 40yd
And the area is 6,000 yd^2
Then we can write:
6,000 yd^2 = (W + 40yd)*W
Now we can solve this for W:
6,000 yd^2 = W^2 + 40yd*W
This is a quadratic equation:
W^2 + 40yd*W - 6,000 yd^2 = 0
The solutions are given by Bhaskara's formula:
[tex]W = \frac{-40 \pm \sqrt{40^2 - 4*1*(-6000)} }{2*1} \\\\W = \frac{-40 \pm 160 }{2}[/tex]
We only care for the positive solution, as the other has no physical sense.
W = (-40yd + 160yd)/2 = 60 yd
And the length is 40yd more than that, so:
L = 60 yd + 40yd = 100yd
If you want to learn more about quadratic equations, you can read:
https://brainly.com/question/1214333