Question

a wire of length 200 cm is cut into two parts and each part is bent to form a square.If the area of the larger square is 9 times that of the smaller square, find the perimeter of the larger square

Answer 1

Answer:

The perimeter of the larger square is $150cm.$

Step-by-step explanation:

First of all, let one part of it be "$x$"

and the other part of it "$200-x$"

Now to solve this :

The area of the square = $L^2$

The area of one part of the square = $x^2$

The area of the other part of the square = $(200-x)^2$

$9x^2= (200-x)^2\\9x^2=40000-400x+x^2$

Now, add, $-4x^2$ to both the sides :

$9x^2-9x^2=40000-400x+x^2-9x^2\\-1(8x^2+400x-40000)=0$

Now, take out the "8" which is common :

$-8(x^2+50x-5000)=0$

Now, divide it by $-8$ :

$x^2+100x-50x-5000=0\\x(x+100)-50(x+100)=0\\(x+100)(x-50)=0$

$x=-100$ or $50$

So, now we know that :

One of the part is = $50cm$

And the other part is = $150cm$

Thus the perimeter of the larger square is = $150cm$