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    Solve this to 2dp:

    2x+3/x-4 - 2x-8/2x+1 = 1

    Really don't understand this problem, what do I have to do? :L
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    (Original post by romansholiday)
    Solve this to 2dp:

    (2x+3)/(x-4) - (2x-8)/(2x+1)

    Really don't understand this problem, what do I have to do? :L
    you would be basically cross multiplying then due to the 2dp you would have to use the quadratic formula im assuming
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    I'm assuming you want the value of x
    Open up the brackets and use the quadratic equation to work it out
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    (Original post by chrlhyms)
    you would be basically cross multiplying then due to the 2dp you would have to use the quadratic formula im assuming
    I forgot to add the = 1 on the end, does this make any difference?
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    (Original post by romansholiday)
    Solve this to 2dp:

    2x+3/x-4 - 2x-8/2x+1 = 1

    Really don't understand this problem, what do I have to do? :L
    cross multiply to get 2x+3(2x+1)- (2x-8)(x-4)/(X-4)(2x+1) = 1 , then times the 1 by the denominator to get 2x+3(2x+1) -(2x-8)(x-4)= (x-4)(2x+1)
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    (Original post by romansholiday)
    I forgot to add the = 1 on the end, does this make any difference?
    yeah because you would have to times the denominators by 1 and then rearrange
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    1. Multiply by (x-4)(2x+1) so it's"
    (2x+3)(2x+1) - (2x-8)(x-4)

    2. Expand the brackets
    4x^2+8x+3 - 2x^2-16x+32
    = 2x^2-8x+35

    3. Solve using the quadratic formula
    a=2, b=-8, c=35
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    (Original post by romansholiday)
    Solve this to 2dp:

    2x+3/x-4 - 2x-8/2x+1 = 1

    Really don't understand this problem, what do I have to do? :L
    Step by step:
    First you expand:
    2x+3(2x+1)- (2x-8)(x-4)/(X-4)(2x+1) = 1
    and then times the 1 by the denominator which equals to:
    2x+3(2x+1) -(2x-8)(x-4)= (x-4)(2x+1)
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    (Original post by GlassyMarbles)
    1. Multiply by (x-4)(2x+1) so it's"
    (2x+3)(2x+1) - (2x-8)(x-4)

    2. Expand the brackets
    4x^2+8x+3 - 2x^2-16x+32
    = 2x^2-8x+35

    3. Solve using the quadratic formula
    a=2, b=-8, c=35
    Wouldn't it be 2x^2-8x-29? Instead of 2x^2-8x+35
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    (Original post by Kiniun)
    Wouldn't it be 2x^2-8x-29? Instead of 2x^2-8x+35
    No idea, did it in a rush. You're probably right though, I tend to make stupid mistakes during multiple-step maths questions.
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    (Original post by GlassyMarbles)
    No idea, did it in a rush. You're probably right though, I tend to make stupid mistakes during multiple-step maths questions.

    If you think that's a stupid step, you should see my 5x2=7 mistakes in exams loool
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    It got x = 25/31. Did anyone else get that?
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    (Original post by Kiniun)
    If you think that's a stupid step, you should see my 5x2=7 mistakes in exams loool
    Hahaha I get you, I wrote 26-16=8 in an exam once
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    (Original post by phat-chewbacca)
    It got x = 25/31. Did anyone else get that?
    I got the same!!! Turns out quadratic formula was unnecessary cuz the x^2s cancel out
 
 
 
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