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    I'm completing the square x^2-6x+11 but I dont know if the answer should be (x-3)^2 + 20 or plus 2 and the same with question x^2-8x+17. can anyone help?
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    (Original post by rosilo)
    I'm completing the square x^2-6x+11 but I dont know if the answer should be (x-3)^2 + 20 or plus 2 and the same with question x^2-8x+17. can anyone help?
    (x-3)^2-9+11

    -9 + 11 =??
    that would be ur constant. Same with the other question
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    (Original post by rosilo)
    I'm completing the square x^2-6x+11 but I dont know if the answer should be (x-3)^2 + 20 or plus 2 and the same with question x^2-8x+17. can anyone help?
    -3 x -3 = 9, so it's +2 to get to 11
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    (Original post by rosilo)
    I'm completing the square x^2-6x+11 but I dont know if the answer should be (x-3)^2 + 20 or plus 2 and the same with question x^2-8x+17. can anyone help?
    Why would it be +20?

    You're essentially doing:

    \displaystyle (x+a)^2=x^2+2ax+a^2\Rightarrow (x+a)^2-a^2=x^2+2ax
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    Thats what I assumed, just wanted to double check, thank you guys
 
 
 
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