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    Hey, just did a maths past paper, easy peasy EXCEPT for this bad boy right here.

    Find the values of a and b when:

    x² - 6x + a = (x + b)²


    I've been going round in circles, can't work it out. Can someone post the answer, and how you get there? cheers
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    cant be bothered
    need a calc and paper to work it out by hand
    but am too tired

    :cool:
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    (Original post by InTeRRoGaToR)
    cant be bothered
    need a calc and paper to work it out by hand
    but am too tired

    :cool:
    haha what's that? you dont know how to do it? never mind, unless you wanna prove me wrong
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    haha
    dnt make me laff
    ur jus tryin to get answer outta me... jus that i really cant be bothered
    and dont bother postin anythin back cos i aint gna look
    so i win
    much love fool
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    Im not an A grade student but won't you have to make it so that x^2 + mx + y = 0 or other. Working on it.
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    someone smarter than "InTeRRoGaToR", sorry, I mean someone with a calculator and more time than "InTeRRoGaToR", can you help me out?
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    (Original post by soulsussed)
    Im not an A grade student but won't you have to make it so that x^2 + mx + y = 0 or other. Working on it.
    could be?
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    you dont need calculator here obviously. I dont think it is possible to find values for a and b, but you can turn a or b into a subject.
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    (Original post by IZZY!)
    you dont need calculator here obviously. I dont think it is possible to find values for a and b, but you can turn a or b into a subject.
    yeh no doubt, but it says "find the values of a and b".. unless it's a typo in the exam paper, but thats quite unlikely
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    I've got a = b^2 +6x so far

    Tell you how I got there:

    x^2 - 6x +a = x^2 + b^2 (-x^2 from both sides)

    -6x + a = b^2 (rearrange by adding 6x)

    a = b^2 + 6x
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    so is the question 100% similar to what you have written?Does it just show the equation and say find the values of a and b?or are the equation written separately?perhaps you may try to solve them separately
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    It's probaby totally wrong as I don't know where to go now.
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    (Original post by hellohello)
    Hey, just did a maths past paper, easy peasy EXCEPT for this bad boy right here.

    Find the values of a and b when:

    x² - 6x + a = (x + b)²


    I've been going round in circles, can't work it out. Can someone post the answer, and how you get there? cheers
    a= 9 and b= -3 would work but I don' know a way of proving that. :confused:
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    (Original post by soulsussed)
    I've got a = b^2 +6x so far

    Tell you how I got there:

    x^2 - 6x +a = x^2 + b^2 (-x^2 from both sides)

    -6x + a = b^2 (rearrange by adding 6x)

    a = b^2 + 6x
    firslly (x+b)^2 isnt x^2 + b^2
    it is x^2 + 2bx+b^2
    secondly you didnt find a value for an a, u turned a into a subject
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    (Original post by IZZY!)
    so is the question 100% similar to what you have written?Does it just show the equation and say find the values of a and b?or are the equation written separately?perhaps you may try to solve them separately
    Yeh, what I wrote in the first post is an exact copy of the question. find the values of a and b, when x²-6x+a=(x+b)²
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    Expanding (x + b)^2 you get, x^2 + 2bx + b^2

    Therefore:

    2b = -6 and b^2 = a

    From there it's an easy solve to get b=-3 and a=9
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    :confused:
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    try to do them separately using the formula
    start with x^2-6x+a=0
    I cant type it on comp cuz i cant find all the symbols and i dont want to go to microsoft word.lol.
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    (Original post by hellohello)
    Hey, just did a maths past paper, easy peasy EXCEPT for this bad boy right here.

    Find the values of a and b when:

    x² - 6x + a = (x + b)²


    I've been going round in circles, can't work it out. Can someone post the answer, and how you get there? cheers
    Ill giv it a go

    x²-6x+a=x²+2bx+b²

    Then Remove like terms

    then: 6x-a=2bx+b²

    therefore:5x-a=2b+b²

    Sh** i'm stuck-lil help plz
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    (Original post by soulsussed)
    :confused:
    Do you not get my solution? Wait... +/- error... ****
    Ok.. now it's correct.
 
 
 
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