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    ok so I've got this math question about algebra- completing the square...
    i dont hav a clue how to answer it... help please?
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    (Original post by #animal-lover)
    ok so I've got this math question about algebra- completing the square...
    i dont hav a clue how to answer it... help please?
    Name:  asd.PNG
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    here is the question....
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    (Original post by #animal-lover)
    Name:  asd.PNG
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    here is the question....
    ok so the coefficient of x^2 is 1, meaning that we can use the general formula for completeting the square:

    x^2 + ax + b = (x+a/2)^2 -(a/2)^2 + b

    Then once u have that formula rearranged to the general formula, u can make it equal to 0 and solve it.
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    wen i saw u were looking for anyone brainy, i was thinking yep defo me, but bruv wat the f is that, is it some made up question or wat?

    In other words cant help u b
    And brainy isnt part of my resume or personality traits
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    (Original post by AKA2234)
    bruv wat the f is that, is it some made up question or wat?
    ...it's the quadratic formula, goddammit!
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    dude i knew that, but i was done with maths last year, literally messed up my brain, forgot everything about it
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    (Original post by brownguytorule)
    ok so the coefficient of x^2 is 1, meaning that we can use the general formula for completeting the square:

    x^2 + ax + b = (x+a/2)^2 -(a/2)^2 + b

    Then once u have that formula rearranged to the general formula, u can make it equal to 0 and solve it.
    soo your saying x^2 = 1??
    so is it gonna be (x+9)^2 + 4= 0???
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    if you are trying to complete the square for

    y = x2 + 18x + 4

    you can start off by dividing the 18 by 2 to get 9...

    y = ( x + 9 )2 + ....

    now think about 92 which is 81.

    how can you reduce 81 down to 4 ?

    minus 77....

    so put it together

    y = ( x + 9 )2 - 77

    after that you have to solve

    ( x + 9 )2 - 77 = 0

    which you can do yourself.
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    the formula for the quadratic equation is: ax^2+bx+c=0
    in your case, a = 1 b = 18 c = 4
    the formula for finding x is:
    x1 = (-b + sqrt(b^2-4ac) ) / 2a
    and
    x2 = (-b - sqrt(b^2-4ac) ) / 2a
    so the answers for that are:
    x1 = (-18 + sqrt(18^2-4*1*4) ) / 2*1 = -9 + sqrt308
    and
    x2 = (-18 - sqrt(18^2-4*1*4) ) / 2*1 = -9 - sqrt308
    cheers
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    (Original post by the bear)
    if you are trying to complete the square for

    y = x2 + 18x + 4

    you can start off by dividing the 18 by 2 to get 9...

    y = ( x + 9 )2 + ....

    now think about 92 which is 81.

    how can you reduce 81 down to 4 ?

    minus 77....

    so put it together

    y = ( x + 9 )2 - 77

    after that you have to solve

    ( x + 9 )2 - 77 = 0

    which you can do yourself.
    Ok so how abt the question: x2+ 12x + 4 = 0
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    (Original post by #animal-lover)
    Ok so how abt the question: x2+ 12x + 4 = 0
    12 divided by 2 = ?

    ?2 = ??

    how do you get from ?? down to 4.... :hmmmm2:
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    (Original post by #animal-lover)
    Ok so how abt the question: x2+ 12x + 4 = 0
    the formula is already given above.

    x1 = -6 + 0.5*sqrt128
    x2 = -6- 0.5*sqrt128
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    (Original post by the bear)
    12 divided by 2 = ?

    ?2 = ??

    how do you get from ?? down to 4.... :hmmmm2:
    12 divided by 2 is 6
    so 62 = 36
    so how do u get from 36 down to 4??
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    (Original post by #animal-lover)
    12 divided by 2 is 6
    so 62 = 36
    so how do u get from 36 down to 4??
    okay... what do you do ?
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    x2+ 12x + 4 = 0

    x= ....... + √..... or x= ........ - √.......

    that is the question on my paper- i have to give a postive and negative answer using that equation....
    the ...... is a space that i have to fill in
    hmmmmm
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    (Original post by #animal-lover)
    x2+ 12x + 4 = 0

    x= ....... + √..... or x= ........ - √.......

    that is the question on my paper- i have to give a postive and negative answer using that equation....
    the ...... is a space that i have to fill in
    hmmmmm
    x= -6 + √32 or x= -6 - √32
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    x = -9 + root(63)
    x = -9 - root(63)
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    its better to google how to solve quadratic equations, mate
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    (Original post by #animal-lover)
    Name:  asd.PNG
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    here is the question....
    x = -9 + square root of 63
    x = -9 - square root of 63

    do you want working out or you just interested in the answer?
 
 
 
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