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    hello,

    can someone tell me what it is x+y =8 cuts the y-axis please can someone tell me the answer please thank you so much
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    (Original post by otrivine)
    hello,

    can someone tell me what it is x+y =8 cuts the y-axis please can someone tell me the answer please thank you so much
    It cuts the y axis at (0,8)

    rearrange equation to give y = 8-x

    which is in form of y = mx + c
    where c is the y intercept

    so c = 8
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    i got it hanks you for your help
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    for example if they say 2x+y=8 cuts the x-aixs do you say

    y=8/2x and the co-ordinate is (4,0)
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    (Original post by otrivine)
    i got it hanks you for your help
    another way to look at it (which is how you must look at it when sketching curves, very important) is that when it cuts the y-axis, the x-value must be zero. So you sub in zero into all the x's in the formula to get the y-intercept
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    brilliant thank you so much for your help ilyking
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    Just substitute y=0 (if looking where it intercepts x axis) or x=0 (if looking where it intercepts y axis) into the equation.
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    what does this question mean :- the line crosses the x-axis and the point A and the y-axis at the point B , and O is the origin find the area of triangle A,B,C and the only to co-ordinates which i am given is (-1,5) (4,-2)
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    please answer soebody
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    A(-1,-2)B(7,2)C(K,4) work out K?
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    please anyone answer 1!!!1
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    (Original post by otrivine)
    what does this question mean :- the line crosses the x-axis and the point A and the y-axis at the point B , and O is the origin find the area of triangle A,B,C and the only to co-ordinates which i am given is (-1,5) (4,-2)
    work out the equation of the line that passes through those two co-ordinates (-1,5) (4,-2) and then use the equation to find out where it crosses the x and y axis. after that you have a triangle so you can work out the area. inbox me if you need any help
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    can someone tell me what is the grade boundaire for C1 edexcel january 2007? thank you
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    (Original post by otrivine)
    can someone tell me what is the grade boundaire for C1 edexcel january 2007? thank you
    Not low enough to help you I fear....
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    (Original post by otrivine)
    can someone tell me what is the grade boundaire for C1 edexcel january 2007? thank you
    Try to focus on getting better at answering the questions first - without stressing about grade boundaries :P Try to actually think about the question and ways to answer them because in the exam there won't be TSR to help you. As to your triangle question, plotting the points on a graph may really help you. Then as someone already said, you'll probably need to find the equation of the lines. :yep:


    --------------

    If you don't know how to find the equation of a straight line given two points, here is one example:

    Points A (1, 5) and B (5, 3) are two points on a straight line. Find the equation of the line in the form y=mx+c

    First find the gradient, m, which is basically change in y divided by change in x.
    For this example, that would be \frac{3-5}{5-1} = -\frac{2}{4} = -\frac{1}{2}

    Plop this into y=mx+c to give you y=-0.5x+c
    Now we need to find c. Pick any point they give you - i'm gonna pick A (1, 5) - and substitute the values in:

    5=-0.5(1)+c
    5=-0.5+c
    c=5.5

    So plop this into y=-0.5x+c and you'll get y=-0.5x+5.5 as the equation of the line.


    Find where AB crosses the y axis

    y=-0.5x+5.5

    Let x=0
    y=-0.5(0)+5.5
    y=5.5

    AB crosses the y axis at (0, 5.5)


    --------------


    (Original post by AnHuman)
    Not low enough to help you I fear....
    That's not too nice lol
 
 
 
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