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    (Original post by thekidwhogames)
    If a quadratic has equal roots thn b^2-4ac=0 is always true e.g. (x-2)^2
    If a quadratic has 2 real distinct roots then b^4-4ac>0 and no roots b^2-4ac<0

    Think about it. If the thing under the root, the discriminant, is 0 then x=-b+-0/2a --> x=-b/2a (one equal root).

    If discriminant > 0 then you have 2 values for the root and hence 2 solutions. If <0, no real root hence no real solutoin.
    Ok thanks man appreciate it, so k would be -4 or +4 then?
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    (Original post by peeked)
    Ok thanks man appreciate it, so k would be -4 or +4 then?
    both
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    (Original post by thekidwhogames)
    both
    yeah yeah that's what i meant, ok nice! thanks man
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    (Original post by Bananasplitxxx)
    Is it k=+-4 then?
    Yes, check my previous reply, just edited it.
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    (Original post by Bananasplitxxx)
    Attachment 727926
    That end part is a pretty massive omission my friend haha
 
 
 
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