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    I really hate these type of questions but it's part of C1 and i need to understand them.

    "Beth and polly are twins and their sister Louise is 2 years older than them. The total of their ages is 32 years.

    Write this information in the form of an equation for L, Louise's age in years"

    They only want the variable L here..... how do i go about eliminating beth and polly variable??? i can only think of forming two equations and subbing it back into the first one?????

    Thanks in advance.
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    yeh just form two equations and solve for L

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    beth and polly = M
    louise = L

    M + 2 = L
    M = L - 2

    2M + L = 32

    2(L - 2) + L = 32
    3L = 36
    L = 12

    i may well have made a mistake though. but you get the idea
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    Beth = A
    Polly = A
    Louise = A+2

    3a+2=32

    (edit

    Beth=L-2
    Polly=L-2
    Louise=L

    3l-4=32
    3l=36
    l=12

    (In context)
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    Look at it from Louise's point of view. She has twin sisters two years younger than her.

    So L + 2(L-2) = 32
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    Oh ok, i get it now.... thanks guys for your help!!!!!
 
 
 
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