Question

The length of a room floor execeds its breadth by 20 m.
The area of the floor remains unaltered when the length
is decreased by 10 m but the breadth is increased by 5
m. The area of the iloor (in square meters) is :
एक कमरे की फर्श की लम्बाई चौड़ाई से 20 मी0 अधिक
है। कमरे की लम्बाई को 10 मी0 से घटा दिया जाता है।
चौड़ाई को 5 मी0 से बढ़ा दिया जाता है, जिसकी कमरे की
क्षेत्रफल पर कोई असर नहीं पड़ता है, तो कमरे का क्षेत्रफल
(a).2800
(c) 300
(b)325
(d)420​

Answer 1

Answer:

Let l is length and b is the breadth

area is l*b

l = b+20

therefore area = (b+20)*b

also area is same when l is reduced by 10 and breadth inc by 5

area = (b+10)*(b+5)

b^2 + 20*b = b*b + 15*b + 50

5*b = 50

b = 10

l = 30

perimeter = 2*(l+b)

2*40 = 80 m

please mark as a brainlist answer ✔

Answer 2

Answer:

(c) 300

Step-by-step explanation:

Let the breadth = x cm

⇒ Length = (x + 20) cm

According to the question,

x(x+20)=(x+10)(x+5)

⇒5x=50

⇒x=10

⇒Area=10(10+20)=300m2

Voila :) Mark me Brainliest :)