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edexcel maths question 9-1 what is wrong with the answer??

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    express 2x^2+20x+7 in the form 2(x+p)^2 +q

    I wrote 2(x+10)^2 +107

    I know something is missing but I don't know since I'm self learning this
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    Factor out a 2 of the first 2 terms then complete the square on the terms inside the bracket
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    Firstly, when you complete the square, when you square the integer inside the bracket, it always becomes negative when it goes outside the brackets.
    Secondly, when you have something like the "2" in front of the brackets, when you have square the integer inside the brackets, you also have to multiply it by this number
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    (Original post by -Phoenix-)
    Firstly, when you complete the square, when you square the integer inside the bracket, it always becomes negative when it goes outside the brackets.
    Secondly, when you have something like the "2" in front of the brackets, when you have square the integer inside the brackets, you also have to multiply it by this number
    thank you, i applied it your solution and got the asnwer 2(x+5)^2-43 which is correct
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    (Original post by TUGBA_AYDIN1)
    thank you, i applied it your solution and got the asnwer 2(x+5)^2-43 which is correct
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