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Core 1: Gradient watch

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    Here is a question I have:

    (p + 3, p - 3), (2p + 4, - p - 5)

    So obviously the gradient equals the change in y over the change in x.

    If I do that I get a different answer to the one in the book, which is -2 but how do I get that answer?

    Thanks!
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    Change in y is 2p+2
    Change in x is -p-1

    Factorise and cancel.
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    Do difference in y/difference in x as you suggest, then look at factorising the top and bottom.
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    (Original post by electriic_ink)
    Change in y is 2p+2
    Change in x is -p-1

    Factorise and cancel.
    But I thought the change in y for example was:

    (- p - 5) - (p - 3) In which case y would be -2p -2...
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    (Original post by Dededex)
    But I thought the change in y for example was:

    (- p - 5) - (p - 3) In which case y would be -2p -2...
    You just subtracted the coordinates the other way round. It doesn't make any difference what way you do them.
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    (Original post by electriic_ink)
    You just subtracted the coordinates the other way round. It doesn't make any difference what way you do them.
    So I get P + 1 on the denominator but how does that cancel with -2p-2?
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    (Original post by Dededex)
    So I get P + 1 on the denominator but how does that cancel with -2p-2?
    That's correct.

    Note that -2p-2 = -2(p+1).
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    (Original post by electriic_ink)
    That's correct.

    Note that -2p-2 = -2(p+1).
    Aah shizen - yes I see...
 
 
 
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