Question

The area of rectangle land is 240cm2. If 8 m decreased from the length it will be a square . Then the length and bredth

Answer 1

Answer:

62cm is breadth

AND, 58 cm is length

Answer 2

Therefore the dimension of the rectangle is 20 cm by 12 cm.

Step-by-step explanation:

Given that, the area of the rectangle is 240 cm².

Let x be the length of the rectangle

If the length is decreased by 8 m, it will be a square.

In a square length= breadth

The length of the rectangle becomes = (x-8) m

Since the rectangle becomes a square, then the breadth of the rectangle = (x-8) cm.

Therefore the length of rectangle = x m

The breadth of the rectangle = (x-8) m

The area of the rectangle is $=[x\times (x-8)]$ cm².

According to the problem,

$x\times (x-8)=240$

$\Rightarrow x^2-8x-240=0$

$\Rightarrow x^2 -(20-12)x-240=0$

$\Rightarrow x^2-20x+12x-240=0$

$\Rightarrow x(x-20)+12(x-20)=0$

$\Rightarrow (x-20)(x+12)=0$

$\Rightarrow x=20,-12$

The value of length can not be negative.

Therefore x=20

Therefore the dimension of the rectangle is x by (x-8)

                                                                        =20 cm by (20-8) cm

                                                                        =20 cm by 12 cm.