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    Given that the equation,
    x² - kx + 5 = 0, k>0 has equal roots. Find the value of k in the form a√b where a and b are integers. (4)can anyone please give me a step by step tutorial on how to solve this question.
    Thank you
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    Help given, edited to remove full solution as it's against the rules
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    (Original post by Swifty139)
    Given that it has equal roots, you should know that the discriminant; b^2 - 4ac, is equal to 0.

    Quadratics are in the form ax^2 + bx + c = 0, so in this case we have a=1, b=-k and c=5. Therefore using our equation:

    (-k)^2 - 4(1)(5) = 0

    k^2 - 20 = 0

    k^2 = 20

    k = root20

    k = 2root5
    Oh I just found it difficult due to the wording in the question, but thank you very much now i understand the concept. I appreciate you giving me a step by step solution on how to solve this problem
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    (Original post by Swifty139)
    Given that it has equal roots, you should know that the discriminant; b^2 - 4ac, is equal to 0.

    Quadratics are in the form ax^2 + bx + c = 0, so in this case we have a=1, b=-k and c=5. Therefore using our equation:

    (-k)^2 - 4(1)(5) = 0

    k^2 - 20 = 0

    k^2 = 20

    k = root20

    k = 2root5
    Don't post full solutions.
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    (Original post by RDKGames)
    Don't post full solutions.
    Why not? Is there some rule i'm unaware of?
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    (Original post by Swifty139)
    Why not? Is there some rule i'm unaware of?
    It's against the forum rules. Refer to the stickies at the top of the forum.

    http://www.thestudentroom.co.uk/show...9#post64637319
 
 
 
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