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Question
Solve:
`( x - 10)(1200/x + 2) = 1260` and x < 0
Solution
Given quadratic equation is `(x - 10)(1200/x + 2) = 1260`
`=> (x - 10)(1200/x + 2) = 1260`
`=>` (x – 10)(1200 + 2x) = 1260x
`=>` 1200x + 2x2 – 12000 – 20x – 1260x
`=>` 2x2 – 12000 – 80x = 0
`=>` x2 – 40x – 6000 = 0
`=>` x2 – 100x + 60x – 6000 = 0
`=>` (x = 100)(x + 60) = 0
`=>` x = 100 or x = – 60
But as x < 0, so x can't be positive.
Hence, x = – 60
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