VERY URGENT - the length of a rectangle exceeds its breadth by 8 cm if length and breadth increase by 6 cm the area of the new rectangle will be 162 sq.cm more than the rectangle. Find the breadth of the given rectangle
Answers
Answer:
let the length be l and breadth be b
the new length be L and new breadth be B
A.T.Q
area = l.b
A = (8+b)b ....1
new area =L.B
162= (14+b)(b+6)
162 = 14b +84 +b^2 +6b
162= 20b + 84 + b^2
76 = 20b + b^2
b^2 + 20b -76 =0
after solving this eq u will get the breadth
Question:-
the length of a rectangle exceeds its breadth by 8 cm. if length and breadth increase by 6 cm the area of the new rectangle will be 162 sq.cm more than the given rectangle. Find the breadth of the given rectangle
Solution:-
Given:-
• The length of the rectangle exceeds it's breadth by 8 cm.
• If length and breadth is increased by
6 cm.
• Then area of new rectangle will be 162cm² more than given rectangle.
Find:-
• The length and breadth of the original rectangle = ?
Formula:-
=> Area of rectangle
= length(L) × breadth(B)
Now, by given,
let, x be the breadth of rectangle so,
for original rectangle.
• breadth = B1 = x ........ ( 1 )
• length = L1 = x + 8 ........ ( 2 )
so, now....
for new rectangle
• breadth = B2 = x + 6 ........ (3)
• length = L2 = x + 8 + 6 ....... ( 4 )
we know, that area of new rectangle will be 162cm² more than given rectangle.
so now,
=> (Area of new rectangle)
- ( 162 cm² )
= (Area of oringinal rectangle)
=> (L2 × B2) - 162 = L1 × B1
=>( x + 8 + 6 ) ( x + 6 ) - 162
= ( x + 8 ) ( x )
=> ( x + 14) ( x + 6 ) - 162 = x² + 8x
=> x² + 6x + 14x + 84 - 162 = x² + 8x
=> x² + 20x -78 = x² + 8x
=> x² - x² + 20x - 8x - 78 = 0
=> 12x - 78 = 0
=> 12x = 78
=> x = 78/12
=> x = 6.5 cm
From ( 1 ),
• breadth = x = 6.5 cm.
From ( 2 ),
• length = x + 8
• length = 6.5 + 8
• length = 14.5cm.
Hence length and breadth of original rectangle is 6.5cm and 14.5cm respectively.
i hope it helps you.