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Question
The area of a rectangular is 640 m2. Taking its length as x cm; find in terms of x, the width of the rectangle. If the perimeter of the rectangle is 104 m; find its dimensions.
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Solution
Let b be the width of the rectangle.
`x` x b = 640
b = `640/x`
Again perimeter of the rectangle is 104 m.
Hence,
`2( x + 640/x )` = 104
x2 - 52x + 640 = 0
( x - 32 )( x - 20 ) = 0
x = 32, 20.
Hence
length = 32 m
width = 20 m.
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