area of big rectangular room is 300m. if the length were decreased by 5 cm and breadth increased by 5 cm. the area would remain unaltered. find the length of the room
Answers
Answered by
82
Hey there,
let x=length of room
let y=breadth of room
area=length*breadth=x*y=300
y=300/x
altered length and breadth:
x-5=length
y+5=breadth
area=(x-5)(y+5)=300
( x - 5) x (300 / x + 5) = 300
(x - 5) x (300 + 5x / x) = 300
(x - 5) x (300 + 5x) = 300x
300x-1500+5x^2-25x=300x
5x^2-25x-1500=0
x^2-5x-300=0
(x+15)(x-20)=0
x=20
length of room=20m
Hope this helps!
let x=length of room
let y=breadth of room
area=length*breadth=x*y=300
y=300/x
altered length and breadth:
x-5=length
y+5=breadth
area=(x-5)(y+5)=300
( x - 5) x (300 / x + 5) = 300
(x - 5) x (300 + 5x / x) = 300
(x - 5) x (300 + 5x) = 300x
300x-1500+5x^2-25x=300x
5x^2-25x-1500=0
x^2-5x-300=0
(x+15)(x-20)=0
x=20
length of room=20m
Hope this helps!
Answered by
18
Answer:
Step-by-step explanation:
Attachments:
Similar questions