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Melanie953
05-26-2009, 04:17 PM
The Question I have is xSqared - 3x - 10 = 0
Thank you :D

Subhotosh Khan
05-26-2009, 04:23 PM
The Question I have is xSqared - 3x - 10 = 0
Thank you :D

Then why are you even trying to do this problem?

For a refresher to:

mathpedia
05-27-2009, 02:28 AM
The Question I have is xSqared - 3x - 10 = 0
Thank you :D

When you have an expression that contains a square root, the best way to solve it, is to separate the square root from the other terms, and then raise the expression to the 2nd power. Of course, first you the condition the term under the square root, to be greater or equal to 0:

x \geq 0

\sqrt{x} - 3*x - 10 = 0 <=> \sqrt{x} = 3*x + 10 <=> x = (3*x + 10)^2 <=> x = (9*x)^2 + 60*x + 100 <=>
( 81*x^2 + 59*x + 100 = 0. From the formula of quadratic equation, we get:x1,2 = \frac{(-59 \pm \sqrt{59*59 - 4*81*100})}{2*81}. Because \sqrt{59*59 - 4*81*100})} < 0 => We have no real solution for your equation.

Denis
05-27-2009, 06:22 AM
The equation is x^2 - 3x - 10 = 0 : NO square root.
(x - 5)(x + 2) = 0