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    arghhh i hate it when i can't do algebra when i know i should be able to....

    The answer i've checked in x=1 but i have nooo idea how to get there and keep coming out with quadratics etc. All help appreciated...


    4/x - 3 = 4/x+3

    thanks in advance
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    If you're coming out with quadratics, can you not use the quadratic equation to solve them?
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    if you times it all through by x(x+3) then you get a very factorisable quadratic- are you sure you've added everything up right?
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    yeah just having a VERY VERY bad night.
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    bring the two fractions on one side. 4/x -4/x+3 = 3
    then times out to get equal denominator which will be (4(x+3) - 4x)/x(x+3) = 3
    the times the denomonator by 3 to get. (4(x+3) - 4x) = 3x(x+3)
    then rearrange and form a quadratic of the form (3x +12)(x-1) then x=1 or x= -12/3 , and your answer is one because either it will say x is positive integer or it is the only x value to satisfy that equation. btw which level is this question, gcses or a level ? thanks i hope that helps
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    if I've understood your question correctly:
    \frac{4}{x}- 3=\frac{4}{x+3}
    multiply by (x+3)x !!! here you have to input the condition x \not= 0 \land x \not= -3
    and you get:
    4(x+3)-3x(x+3)=4x
    12-3x(x+3)=0
    x^2+3x-4=0
    (x+4)(x-1)=0
    x=1 \lor x=-4
    QED
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    we're doing it as A2 level. Core 3 AQA
 
 
 
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