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प्रश्न
The area of rectangle is `192cm^2` and its perimeter is 56 cm. Find the dimensions of the rectangle.
उत्तर
Area of the rectangle `192 cm^2`
Perimeter of the rectangle 56 cm
Perimeter = 2(length + breath)
⇒`56=2(l+b)`
⇒`l+b=28`
⇒` l=28-b`
`"Area"="Length" xx "breath"`
⇒`192=(28-b)xb`
⇒`192=28b-b^2`
⇒`b^2-28b+192=0`
⇒`(b-16) (b-12)=0`
⇒` b=16 or 12`
Thus, we have;
`l=28-12`
⇒`l=28-12`
⇒` l=16`
We will take length as 16 cm and breath as 12 cm because length is greater than breath by convention.
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