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    In a maths challenge there are 45 questions
    A correct answer is awarded 5 points and incorrect answer is awarded -2 points.
    Ben answered all questions and is awarded 113 points in the competition.
    Use these equations to find how many questions ben answered correctly.

    Help please!
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    Set up an equation yourself using the information given, then start to eliminate or substitute like a normal simultaneous equation or so.
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    Iv got 5x+(-2y)=113 but I can't think of a second?
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    (Original post by ross2000)
    Iv got 5x+(-2y)=113 but I can't think of a second?
    Have you do considered making an equation on the total amount of questions?
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    (Original post by ross2000)
    Iv got 5x+(-2y)=113 but I can't think of a second?
    So if we take x as being the no of correct questions and y being the number of wrong questions and there are 45 questions in total. Could you could up with an equations to express that?
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    (Original post by Slowbro93)
    Have you do considered making an equation on the total amount of questions?
    I have, just no idea which numbers to use for this question or the next 3...
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    (Original post by KaylaB)
    So if we take x as being the no of correct questions and y being the number of wrong questions and there are 45 questions in total. Could you could up with an equations to express that?
    Thanks so much, I got 29 correct 16 wrong which seems right.

    Now onto the last 3...
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    (Original post by ross2000)
    Thanks so much, I got 29 correct 16 wrong which seems right.

    Now onto the last 3...
    No problem, happy to help
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    How could I put (12,6) with y intercept of 2 into an equation to prove its equation (straight line)

    Very confused about this
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    (Original post by ross2000)
    How could I put (12,6) with y intercept of 2 into an equation to prove its equation (straight line)

    Very confused about this
    If you know the y intercept is 2, what would that be as a co-ordinate?
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    I love simultaneous equations
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    Don't take my word but looking at this, you could only assume the second set of coordinates are 0,2 right? If the intersection of y is at 2. So using y = mx +c start to sub in values. Y = mx + 2. Now use both coordinates to find the gradient which is given as the change in y divided by the change in x... So 6-2/12 so 4 divided by 12. And then plug that into the MX part so it would be y = 4/12x + 2

    Hopefully someone will give you the full right answer this is just an assumption
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    (Original post by KaylaB)
    If you know the y intercept is 2, what would that be as a co-ordinate?
    I see, so I have 3y-x=6 and 3y=1/3x + 2 (where 1/3 is gradient for y=mx+c)

    Think i've got it...
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    (Original post by ross2000)
    I see, so I have 3y-x=6 and 3y=1/3x + 2 (where 1/3 is gradient for y=mx+c)

    Think i've got it...
    If you mean 3y-x=6 and y=1/3x +2 then yes, there both the same.
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    (Original post by KaylaB)
    If you mean 3y-x=6 and y=1/3x +2 then yes, there both the same.
    Thanks! It's far too late for maths
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    (Original post by ross2000)
    Thanks! It's far too late for maths
    No problem! But it's never too late for maths!
 
 
 

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