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    Solve the following equation, giving your answer in the form of k \sqrt 2

    z\sqrt {32} - 16 = z\sqrt {8} - 4

    The answer is  z = 3\sqrt {2}

    Can somebody pls show me how you worked it out,

    Thanks
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    (Original post by Bleak Lemming)
    Solve the following equation, giving your answer in the form of k \sqrt 2

    z\sqrt {32} - 16 = z\sqrt {8} - 4

    The answer is  z = 3\sqrt {2}

    Can somebody pls show me how you worked it out,

    Thanks
    First gather the terms containing z on one side and the ones that don't on the other. Then rewrite the surds and multiples of sqrt2 and take a factor of z out and rearrange to make z the subject.
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    Take your Zs to one side, and your numbers to the other. Factorize out your Zs on the Z side (so you get Z*(something-something)) then you can figure out the surds in the bracket and then solve it like any other linear equation.
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    (Original post by JoMo1)
    Take your Zs to one side, and your numbers to the other. Factorize out your Zs on the Z side (so you get Z*(something-something)) then you can figure out the surds in the bracket and then solve it like any other linear equation.
    (Original post by Rup)
    oks
    Ok I've got as far as

    z (4\sqrt{2} - 2\sqrt{2}) = 12



z(2\sqrt{2}) = 12



2z\sqrt{2} = 12



z\sqrt{2} = 6

    This isn't going the right way here :s
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    (Original post by Bleak Lemming)
    Ok I've got as far as

    z (4\sqrt{2} - 2\sqrt{2}) = 12



z (2\sqrt{2}) = 12



2z\sqrt{2} = 12



z\sqrt{2} = 6

    This isn't going the right way here :s
    That's right now divide through by sqrt2, remembering that 6=3x2 and 2/sqrt2=sqrt2.
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    I got the answer as 6/root 2, which works.
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    (Original post by Bleak Lemming)
    Ok I've got as far as

    z (4\sqrt{2} - 2\sqrt{2}) = 12



z(2\sqrt{2}) = 12



2z\sqrt{2} = 12



z\sqrt{2} = 6

    This isn't going the right way here :s
    yeah it is lol
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    (Original post by Gemini92)
    That's right now divide through by sqrt2, remembering that 6=3x2 and 2/sqrt2=sqrt2.
    Thanks!

    got there in the end :]
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    C1 is nothing to worry abt....its jus apiece of cake! Whats really tough for me was Stats! however my hard work paid off at the end! Right now i m standing proud with an overall A in Maths, hehe!
 
 
 
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