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SC2312
Mar 20, 2012, 12:34 AM
Kylie bought an item for $x and sold it for $10.56. If Kylie lost x per cent, find x.

Kahani Punjab
Mar 20, 2012, 02:42 AM
SC2312,

You are welcome to this site. In your statement, the purchase value is put to be same as the %age loss, which is not possible. Please look into your statement again. If %age loss is y, then -
x - 10.56 = y

And, %age loss is 100.y/x

SC2312
Mar 20, 2012, 03:52 AM
the question from my textbook is.

Kylie bought an item for $x and sold it for $10.56. If Kylie incurred a loss of x per cent, find x. (To solve, it is said you have to form a quadratic equation)

Kahani Punjab
Mar 21, 2012, 10:49 AM
SC2312,

As the %age loss is also x, the equation will be as follows -

(x - 10.56) *100 / x = x

(x - 10.56) *100= x*x

(x - 10.56) *100= x^2

(100 x - 1056) = x^2

x^2 -100 x + 1056 = 0

I think you can solve it now, but still if you face problem, I can solve it for you.

SC2312
Mar 21, 2012, 01:21 PM
Hello thank you for that, but apparently my textbook has the answers at 12 and 88. Which is not true if you put it into your equation. Is there another way to do it?