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    i tried to find what L = by doing root 16x^2 + 12x^2 with pythagoras
    i then got that 2160pi/pi = 12x (root16x^2+12x^2)
    im not to sure if thats right and i dont know what to do next? thanks
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    (Original post by Gent2324)
    i tried to find what L = by doing root 16x^2 + 12x^2 with pythagoras
    i then got that 2160pi/pi = 12x (root16x^2+12x^2)
    im not to sure if thats right and i dont know what to do next? thanks
    You're right so far. You now need to simplify root(16x^2 + 12x^2). 16x^2 + 12x^2 simplifies to 28x^2. What is root(x^2)?
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    (Original post by tiny hobbit)
    You're right so far. You now need to simplify root(16x^2 + 12x^2). 16x^2 + 12x^2 simplifies to 28x^2. What is root(x^2)?
    so its root 28x^2 which is 2root7x?
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    (Original post by Gent2324)
    so its root 28x^2 which is 2root7x?
    Yes. You should now be able to solve the equation to find x

    Whoops, I wasn't concentrating at the beginning. You didn't square the 16 and the 12 when using pythagoras.
    So L^2 = 256x^2 + 144x^2 = 400 x^2 That makes the numbers much easier. I spotted this when I wondered how V was going to turn out to be an integer.
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    (Original post by tiny hobbit)
    Yes. You should now be able to solve the equation to find x.
    im not to sure how to do that, how do i do 12 times 2root7x?
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    (Original post by Gent2324)
    im not to sure how to do that, how do i do 12 times 2root7x?
    Go back to the previous post where I explain that I was an idiot. The numbers are now much simpler.
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    (Original post by tiny hobbit)
    Go back to the previous post where I explain that I was an idiot. The numbers are now much simpler.
    ok so i got 2160pi/pi= 240x because root 400x^2 = 20x and 20x x 12 = 240x, am i suppose to divide 2160pi/pi by 240?
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    (Original post by Gent2324)
    ok so i got 2160pi/pi= 240x because root 400x^2 = 20x and 20x x 12 = 240x, am i suppose to divide 2160pi/pi by 240?
    It should be 240x^2 as it was 12x (this shows the danger of using x for the letter and for the times sign). Yes divide to get the value of x^2 then square root it.
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    (Original post by tiny hobbit)
    It should be 240x^2 as it was 12x (this shows the danger of using x for the letter and for the times sign). Yes divide to get the value of x^2 then square root it.
    ah yes i got it now thank you!
 
 
 
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