Question

Find the dimensions of rectangle whose perimeter is 28 and whose area is 40 square metres ?

Answer 1

Hello..

Here is Your Answer.

Given :- Perimeter of rectangle = 28

2 (l + b ) = 28 

l + b = 14 

l = 14 - b --- (i)

area = 40 

l × b = 40 

from (i)

( 14 -b ) × b = 40 

(14 - b²) = 40

b² - 14b + 40 = 0

After spilliting the zeros you will get...


(length) = 10
(breadth) = 4

Answer 2

HEYA!!!!

Here is your answer :

Given,

Perimeter of rectangle = 28mts

2 ( l + b ) = 28

2 (l + b ) = 28

l + b = 28/2

l + b = 14

l = 14 - b ---------(1)

Now area of rectangle = 40

l × b = 40

from eq 1

( 14-b ) × b = 40

$(14 - b) \times b= 40 \\ \\ (14 - \ {b^{2} } ) = 40 \\ \\ {b }^{2} - 14b + 40 = 0 \\ \\ after \: splitting \: th e \: zeros\: \\ \\ \\ {b}^{2} - 4b - 10b + 40 = 0 \\ \\ b(b - 4) - 10(b - 4) = 0 \\ \\ b - 4 = 0 \: \: \: \: \: b - 10 = 0 \\ \\ b = 4 \: \: \: \: \: \: b = 10$

Therefore, length of rectangle = 10 , breadth of rectangle =4..

HOPE THIS HELPS U. . .