Question

Thr length of a room floor exceeds its breadth by 20m .the area of the floor remains unaltered when the length is decreased by 10m but the breadth is increased by 5m . the perimeter of the floor in the former is

Answer 1

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

Answer 2

Answer:

length is reduced, then (x-10)(x+5) will come