Help! Maths!

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    I'm not sure if I've done it correctly, so I wanted to double check the answer. The question is as follows:
    w,x and y are three integers
    w is 2 less than x
    y is 2 more than x
    Prove that wy + 4 =x^2
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    so w = x -2
    y = x+2
    Set wy + 4 = L.H.S. and try to work it through from there!
    the thread title made me laugh lol, reminds me of my first year at college
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    (Original post by k.russell)
    so w = x -2
    y = x+2
    Set wy + 4 = L.H.S. and try to work it through from there!
    the thread title made me laugh lol, reminds me of my first year at college
    The way I did it was by giving x a value of 1, and worked on from there, would that be correct? So w became -1 and y became 3
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    (Original post by Botcampers)
    I'm not sure if I've done it correctly, so I wanted to double check the answer. The question is as follows:
    w,x and y are three integers
    w is 2 less than x
    y is 2 more than x
    Prove that wy + 4 =x^2
    w=x-2

    y=x+2

    wy=(x-2)(x+2)

    Expand. Rearrange.
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    (Original post by Botcampers)
    The way I did it was by giving x a value of 1, and worked on from there, would that be correct? So w became -1 and y became 3
    no need to plug in numbers! this is algebra m8 no numbers allowed (apart from coefficients). In all seriousness, the substitution you should be making is to get y and w in terms of x then rearrange to prove that what you have is = to x^2
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    Hi, this is my solution to your question.

    w = x-2
    y = x+2
    wy - (x-2)(x+2) - Difference of two squares
    - x^2 - 2^2
    - x^2 - 4
    wy + 4 = x^2 - 4 + 4
    4s cancel it out so is just x^2

    Hope that helped!!
 
 
 
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