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.

Answer 1

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.