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    Find the value of 5/ (square rooted) X /20.

    /5 + /20 = k/5, where k is an integer.

    Find value of k.

    Find value of /5 + /45 divided by /20.

    (Non calculator)
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    (Original post by Eddie87-04)
    Find the value of 5/ (square rooted) X /20.

    /5 + /20 = k/5, where k is an integer.

    Find value of k.

    Find value of /5 + /45 divided by /20.

    (Non calculator)
    First question is too ambiguous. Do you mean: (5/√x)/20, or 5/(√x/20) ?

    The second one, there are no numerators on the left hand side... :confused:
    Same with the third.

    If I took them to mean (1/5 + 1/45)/20, then:

    (9/45 + 1/45)/20
    (10/45)/20
    (10/45)*(1/20)
    10/900
    1/90
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    Thanks. I mean the square root of 5 X the square root of 20.

    square root of 5 + square root of 20 = k/5, where k is the integer.

    Then it says find value of k.


    Then find the value of sqaure root of 5 + square root of 45 divided by square root of 20.

    How do you do this with out a calculat
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    (Original post by Eddie87-04)
    Find the value of 5/ (square rooted) X /20.

    /5 + /20 = k/5, where k is an integer.

    Find value of k.

    Find value of /5 + /45 divided by /20.

    (Non calculator)
    Nor sure what the first one means, but the others, ...

    √5 + √20 = k/5
    5 + 2√(5*20) + 20 = k²/5²
    2*10 + 25 = k²/25
    25*45 = k²
    k = 5*3√5
    k = 15√5
    ======

    (√5 + √45)/√(20)
    √5/√(20 + √(45)/√(20)
    √(1/4) + √(225/100)
    1/2 + 15/10 = 5/10 + 15/10 = 20/10 = 2
    ==========================
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    (Original post by Eddie87-04)
    Thanks. I mean the square root of 5 X the square root of 20.

    ...

    How do you do this with out a calculat
    √5 * √20
    = √(5*20)
    = √(100)
    = 10
    ===
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    (Original post by Eddie87-04)
    Thanks. I mean the square root of 5 X the square root of 20.

    square root of 5 + square root of 20 = k/5, where k is the integer.

    Then it says find value of k.


    Then find the value of sqaure root of 5 + square root of 45 divided by square root of 20.
    sqrt(5) * sqrt(20) = sqrt(100) = 10

    sqrt(5) + sqrt(20) = sqrt(5) + sqrt(4*5) = sqrt(5) + 2sqrt(5) = 3sqrt(5)
    Hence, k = 3

    (sqrt(5) + sqrt(45))/sqrt(20) = (sqrt(5) + 3sqrt(5))/2sqrt(5) = 4sqrt(5)/2sqrt(5) = 2
 
 
 
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