Math, asked by zerrinsaumik, 1 year ago

the perimeter of a rectangle is 30cm, the area of the rectangle is 50cm square.find the length of the rectangle

Answers

Answered by mahekagrawal61
8
2L+2W= perimeter = 30 
L*w =Area = 50 
L*W=50 l= 50/w 
2L + 2W = 30 
2*50/w +2W= 30 
100/W + 2W=30 
100+2W^2 / w = 30 
100+2W^2= 30 W 
2W^2-30W+100=0 
W^2-15W+50=0 
W^2-10W-5W+50=0 
W(W-10)-5(w-10)=0 
(W-5)(W-10)=0 
W= 5 Or 10 

Hope it will help u.... ✌✌
Plzz mark as brainlist ..
Answered by bilalkhanb
0

Length of the rectangle  will be 10 cm

Step-by-step explanation:

The area of rectangle = 50 cm square

                        L x B     =  50 cm square

                              B  =  (50 cm square) / L    ...................Eq. No. 1

The perimeter of the rectangle = 30 cm

                                   2 X ( L + B )  = 30 cm

                                   2 L + 2 B = 30 cm

                      2 L + 2 x (50 cm square/L) = 30 cm   ...................From Eq. No. 1

                     2 L + (100 cm square / L)   = 30 cm

                         ( 2 L^2 + 100 cm square ) = L x 30 cm

                           2 L^2 + 100 - 30 L = 0            

                           2 L^2 - 30 L + 100  = 0

                            2 (L ^2 - 15 L + 50 ) = 0

                             (L ^2 - 15 L + 50 ) = 0/2

                             (L ^2 - 15 L + 50 ) = 0

                             {L^2 - (5 + 10) L + 50}  = 0

                             (L^2 - 5L - 10L + 50)  = 0

                             L (L - 5) - 10 ( L - 5 ) = 0

                             (L - 5) ( L - 10 )  = 0

Now,

                       Taking ( L - 5 ) =0

                                  L = 5 cm

                       Taking ( L - 10 ) =0

                                  L = 10 cm            

There are two values, to check the correct we have to do the following process:  

On putting the first value of L in equation 1, we get:

                           B  =  (50 cm square) / 5

                           B = 10 cm square

Here we can see the value of Breadth > Length which is not possible practically.

 So, the second value will be right i.e. L = 10 cm

Know More:

Q.1. Each side of a rectangle is doubled.Find the ratio between- perimeter of the original rectangle and the resulting rectangle, and area of the original rectangle and the resulting rectangle

Click Here: https://brainly.in/question/2911026

Q.1. If the diagonal of a rectangle is 25m long and perimeter of the rectangle is 70m.Find the area of rectangle.??

Click Here: https://brainly.in/question/3015557

Similar questions