Question: A rectangular meadow has an area of 247 sq.m. and its perimeter is 64m, find the length and breadth of the meadow.
Solution:
Given,
Area of the rectangular meadow (A) = 247 m²
Perimeter of the meadow (P) = 64 m
Let the length and breadth of the same rectangular meadow be l m and b m respectively.
We have,
P = 64
$or, 2(l+b) = 64$
$or, 2(l+b) = 2×32$
$or, l+ b= 32$
$or, l = 32-b$ - (i)
Also,
A = 247
$or, lb = 247$
[ Put value of l from equation (i) ]
$or, (32-b)b = 247$
$or, 32b - b² = 247$
$or, b² -32b +247 = 0$
$or, b² -(19+13)b +247 = 0$
$or, b² -19b -13b +247 = 0$
$or, b(b -19) -13(b -19) = 0$
$or, (b -13)(b -19) = 0$
Either
$b -13 = 0$
$\therefore b = 13$
Or,
$b -19 = 0$
$\therefore b = 19$
Since, we take breadth is always shorter than the length. Put value of b = 13 in equation (i), we get,
$l = 32-13$
$\therefore l = 19$
So, (l,b) = (19,13)
Therefore, the required length and breadth of the rectangular meadow are 19m and 13m respectively.
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