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When does the quadratic equation -x^2+3x+A=0 have two distinct real roots? watch

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    The quadratic equation of -x^2+3x+A=0 gets the answers of x=5 or x=-2 but not sure about the real roots. Thank you for any help
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    (Original post by Rebecca Porter)
    The quadratic equation of -x^2+3x+A=0 gets the answers of x=5 or x=-2 but not sure about the real roots. Thank you for any help
    B^2 - 4ac is 9 + 4A. (Discriminant)

    So actually, for certain values of A there aren't real roots.

    As you've got x=5 and x=2 you must have found or been given what A is at some point. Is this helpful?
 
 
 
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