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    Here are some questions I sturggle with.

    1.The line y=x+2 meets the curve x^2+4y^2-2x=35 at the point a and b find co ordinates of a and b.

    What I did was input one equation into the other : x^2+4(x+2)(x+2)-2x=35 which equals 5x^2+14x-19 and the solutions to this is x=19/5 and x=1
    the problem is that a and b do not pass through the x or y-axis.

    2 (4 part question managed to do the first 2 parts)

    (a) Find equation of line joining A(7,4) and B(2,0) gve answer in ax+by+c=0 format so 4x-5y-8=0

    (b)Find length of AB in surd form

    4-0=4 7-2=5
    square root of 4^2+5^2 which is the root of 41.

    (c)The point C has coordinate (2,t) where t>0 and AC=AB
    find value of t

    (d)Find area of triangle ABC

    I cannot do c and b.
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    (Original post by Anonymous1502)
    Here are some questions I sturggle with.

    1.The line y=x+2 meets the curve x^2+4y^2-2x=35 at the point a and b find co ordinates of a and b.

    What I did was input one equation into the other : x^2+4(x+2)(x+2)-2x=35 which equals 5x^2+14x-19 and the solutions to this is x=19/5 and x=1
    the problem is that a and b do not pass through the x or y-axis.
    I think your first x-coordinate should be -19/5, but otherwise this is fine. Why do you think that either point should lie on the axes (if this is what you are saying, I'm not quite sure how a point can pass though an axis)?
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    (Original post by Pangol)
    I think your first x-coordinate should be -19/5, but otherwise this is fine. Why do you think that either point should lie on the axes (if this is what you are saying, I'm not quite sure how a point can pass though an axis)?
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    (Original post by Anonymous1502)
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    But A and B do clearly not lie on the axes. You need to find the y-coordinates that go with the x-coordinates you have found, and then the line that passes through both of these points will cut through the axes as shown in the diagram.
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    (Original post by Pangol)
    But A and B do clearly not lie on the axes. You need to find the y-coordinates that go with the x-coordinates you have found, and then the line that passes through both of these points will cut through the axes as shown in the diagram.
    How would you find the y cordinates?
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    (Original post by Anonymous1502)
    How would you find the y cordinates?
    You know that the points lie on the line y=x+2 and the curve x^2+4y^2-2x=35. Substitute the x-coordinates into one of these. One is considerably easier than the other!
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    (Original post by Pangol)
    You know that the points lie on the line y=x+2 and the curve x^2+4y^2-2x=35. Substitute the x-coordinates into one of these. One is considerably easier than the other!
    y=x+2 becomes y-2=x so (y-2)(y-2)+4y^2-2(y-2)=35
    y^2-4y+4+4y^2-2y-4=35
    5y^2-6y-35=0 which cannot be factorised.
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    (Original post by Anonymous1502)
    y=x+2 becomes y-2=x so (y-2)(y-2)+4y^2-2(y-2)=35
    y^2-4y+4+4y^2-2y-4=35
    5y^2-6y-35=0 which cannot be factorised.
    There is no need to do this. You know that y = x + 2. And you know the x-coordinates already. So you can easily find the y-coordinates.
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    (Original post by Pangol)
    There is no need to do this. You know that y = x + 2. And you know the x-coordinates already. So you can easily find the y-coordinates.
    y=1+2 y=-19/5+2
    y=3 y=-9/5
 
 
 
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