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    Hello everyone, Can someone please help solve this for me and then explain it as if you're speaking to an idiot please?

     (\sqrt7 + \sqrt7)^2 =
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    Three things you need to know here:
    1. a + a = 2a
    2. (pq)^2 = p^2q^2
    3. \left( \sqrt{z} \right)^2 = z

    Think what a might be with relation to this question, and then think what p and q might be... then z will be quite obvious.
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    Is the answer 98?
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    (Original post by e-lover)
    Hello everyone, Can someone please help solve this for me and then explain it as if you're speaking to an idiot please?

     (\sqrt7 + \sqrt7)^2 =
    I presume you mean expand or simplify. You should not use the word 'solve'
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    (Original post by e-lover)
    Hello everyone, Can someone please help solve this for me and then explain it as if you're speaking to an idiot please?

     (\sqrt7 + \sqrt7)^2 =
     (\sqrt7 + \sqrt7)^2 = (\sqrt7 + \sqrt7)(\sqrt7 + \sqrt7)

    now try and solve it as a quadratic.

    Does this help?
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    (Original post by steve2005)
    I presume you mean expand or simplify. You should not use the word 'solve'
    You're talking to a mathmo idiot, sir :yes: :p:
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    (Original post by e-lover)
    Is the answer 98?
    Nope.

    Here are some steps; try and do it without expanding them all:
    Step 1
    \newline \sqrt{7} + \sqrt{7} = 2\sqrt{7}

    Step 2
    \newline (2 \sqrt{7})^2 = 2^2 \times (\sqrt{7})^2

    Step 3
    \newline 2^2 \times (\sqrt{7})^2 = 4 \times 7

    Step 4
    \newline 4 \times 7 = 28


    (Original post by gemmalouise)
     (\sqrt7 + \sqrt7)^2 = (\sqrt7 + \sqrt7)(\sqrt7 + \sqrt7)

    now try and solve it as a quadratic.

    Does this help?
    Spoiler:
    Show
    What's the point in doing that when (\sqrt7 + \sqrt7)^2 = (2\sqrt{7})^2?
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    (Original post by gemmalouise)
     (\sqrt7 + \sqrt7)^2 = (\sqrt7 + \sqrt7)(\sqrt7 + \sqrt7)

    now try and solve it as a quadratic.

    Does this help?
    Does that make the answer 28 then?
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    (Original post by e-lover)
    Does that make the answer 28 then?
    by my calculations, yes.
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    (Original post by gemmalouise)
    by my calculations, yes.
    Yayyyyy!!!!!!

    Can I get a confirmation?
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    Confirmed
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    Thank you very much to everyone for helping me 'solve' that. I can now live a full and varied life again.
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    (Original post by e-lover)
    Thank you very much to everyone for helping me 'solve' that. I can now live a full and varied life again.
    what did you need it for?
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    (Original post by e-lover)
    Hello everyone, Can someone please help solve this for me and then explain it as if you're speaking to an idiot please?

     (\sqrt7 + \sqrt7)^2 =
    expand the brackets to get

    (sqrt7 + sqrt7) x (sqrt7 + sqrt7)

    then expand the brackets to get 7 + 7 + 7 + 7

    you should then get an answer of 28

    hope that helps
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    (Original post by Ben77mc)
    what did you need it for?
    For a test I'm working for. It's one of those standardized ones.
 
 
 
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