Cut a rectangular piece of iron with an area of 150cm2 and its length is 5cm longer than its width.What are the width and length of this pece of iron?
steps and answer thx
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Let the length be x cm and the width be y cm
xy = 150 ........(1)
x - y = 5 .........(2)
From (2): x = 5+y ..........(3)
Put (3) into (1):
y(5+y) = 150
5y + y² = 150
y² + 5y - 150 = 0
y = 10 or y = -15(rej.)
∵y = 10
∴ x = 15
∴The required length and width are 15cm and 10cm respectively
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