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Simmultaneous question that i got wrong...please be elaborate in your working out Watch

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    Calculate the coordinate of the points or intersection of the straight line 2x+3y=10 and the curve 2/x + 3/y = 5
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    We are not allowed to give full answers :cry:

    rearrange the first equation to make x the subject.

    put the expression for x into the second equation.

    rearrange... you normally end up with a quadratic ?

    solve the quadratic to find your two x values

    find the y values from the first equation.
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    (Original post by TumiZN)
    Calculate the coordinate of the points or intersection of the straight line 2x+3y=10 and the curve 2/x + 3/y = 5
    Is this calculus
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    (Original post by TumiZN)
    Calculate the coordinate of the points or intersection of the straight line 2x+3y=10 and the curve 2/x + 3/y = 5
    Multiply both sides by xy

    This means x and y are cancelled out., giving us

    2x+3y=5xy

    Minus -5xy from both sides,

    Which gives us 2x+3y-5xy=0

    Minus -3y from both sides

    This gives us

    2x-5xy=-3y


    Then find the common factor, in this case on the left hand side, it is x.

    so

    x(2-5y) =-3y

    Divide both sides by (2-5y)

    x= -3y / 2-5y
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    (Original post by the bear)
    We are not allowed to give full answers :cry:
    the thing is I already know the correct answers all I want to see is the proper working out so I can see where I went wrong
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    (Original post by TumiZN)
    the thing is I already know the correct answers all I want to see is the proper working out so I can see where I went wrong
    http://www.webmath.com

    If you input the equations etc in there, it will give you a breakdown (yes, step by step!) so you can see where your going right/wrong
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    I re wrote second eq as 2x^-1 + 3y^-1 =5 then got stuck id like to see a walkthrough too!
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    (Original post by TumiZN)
    the thing is I already know the correct answers all I want to see is the proper working out so I can see where I went wrong
    all we can do is look at your version ?
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    (Original post by apronedsamurai)
    http://www.webmath.com

    If you input the equations etc in there, it will give you a breakdown (yes, step by step!) so you can see where your going right/wrong
    thanks
 
 
 
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