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    5. Solve the equation
    2logx=log4 + log (2x+5)
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    Can you combine 2logx - log(2x+5) using the log rules?
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    (Original post by vc94)
    Can you combine 2logx - log(2x+5) using the log rules?
    which log rule do i use for that?
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    (Original post by princess271)
    5. Solve the equation
    2logx=log4 + log (2x+5)
    What I did...

    I re-wrote the expression....

    logx^2=log4+log(2x+5)

    I then used two of the log rules to do this...

    10^(logx^2)=10^log4(2x+5)

    You then get a quadratic equation to solve...
    x^2=4(2x+5)
    x^2=8x+20

    Solution

    X=10
    x=-2

    I hope this doesn't confuse you
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    (Original post by JunePlum)
    What I did...

    I re-wrote the expression....

    logx^2=log4+log(2x+5)

    I then used two of the log rules to do this...

    10^(logx^2)=10^log4(2x+5)

    You then get a quadratic equation to solve...
    x^2=4(2x+5)
    x^2=8x+20

    Solution

    X=10
    x=-2

    I hope this doesn't confuse you
    thank you
    ^ is that a squared sign?
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    (Original post by princess271)
    thank you
    ^ is that a squared sign?
    Yes
    x^2 means x 'squared'
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    (Original post by JunePlum)
    Yes
    x^2 means x 'squared'
    ok thanks
 
 
 
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