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    Evil maths strikes back at me! I absolutely hate maths although I can do most of it, but sometimes, I get problems and this is one...

    So here is my problem, I'm just a bit confused. Teacher says set equation to 0 (already is,) factorise - well I get confused because there's like 3 ways to factorise and then solve.

    (2x+5) (3x-2) = 0

    Now it's probaly not very hard but I'm very confused with all the factorising. I don't know whether to cancel out (6x^2 etc etc) or solve it.

    Thanks for your help.
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    (Original post by gemgems89)
    Evil maths strikes back at me! I absolutely hate maths although I can do most of it, but sometimes, I get problems and this is one...

    So here is my problem, I'm just a bit confused. Teacher says set equation to 0 (already is,) factorise - well I get confused because there's like 3 ways to factorise and then solve.

    (2x+5) (3x-2) = 0

    Now it's probaly not very hard but I'm very confused with all the factorising. I don't know whether to cancel out (6x^2 etc etc) or solve it.

    Thanks for your help.

    What is it you're trying to do? Solve it?
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    There are 2 solutions to the equation:

    2x+5 = 0 or 3x-2 = 0

    <=> x = -5/2 or x = 2/3

    Hope this helps.
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    (Original post by MadNatSci)
    What is it you're trying to do? Solve it?
    isn't it already solved?
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    (Original post by gemgems89)
    Evil maths strikes back at me! I absolutely hate maths although I can do most of it, but sometimes, I get problems and this is one...

    So here is my problem, I'm just a bit confused. Teacher says set equation to 0 (already is,) factorise - well I get confused because there's like 3 ways to factorise and then solve.

    (2x+5) (3x-2) = 0

    Now it's probaly not very hard but I'm very confused with all the factorising. I don't know whether to cancel out (6x^2 etc etc) or solve it.

    Thanks for your help.

    Hi this is what i got, check it with someone just in case im not right, but i think i am

    1. (2x+5) (3x-2)=0
    2. 6x^2-4x+15x=10
    3. 6x^2+12x=10
    4. factorise 6x(x+2)=10
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    Hey,

    The way to solve this is like your teacher says, set the equation to zero.

    (2x+5) (3x-2) = 0

    Having done this, you know that either (2x+5) = 0, or (3x-2)=0, as there are two factors in the equation, so if one of them is zero, it doesn't matter what the other one is, the product will be zero too.

    If 2x+5 = 0, then:

    2x = -5

    so: x = -5/2

    Alternatively, if: 3x-2 = 0,

    then: 3x = 2,

    x = 2/3

    So the two possible values for x are -5/2 and/or 2/3.

    Hope this helps

    G
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    (Original post by gzftan)
    Hey,

    The way to solve this is like your teacher says, set the equation to zero.

    (2x+5) (3x-2) = 0

    Having done this, you know that either (2x+5) = 0, or (3x-2)=0, as there are two factors in the equation, so if one of them is zero, it doesn't matter what the other one is, the product will be zero too.

    If 2x+5 = 0, then:

    2x = -5

    so: x = -5/2

    Alternatively, if: 3x-2 = 0,

    then: 3x = 2,

    x = 2/3

    So the two possible values for x are -5/2 and/or 2/3.

    Hope this helps

    G
    Yes, thanks everyone. I just never know how to factorise which bit. Still a bit confused but the answer makes sense.
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    (Original post by gzftan)
    Hey,

    The way to solve this is like your teacher says, set the equation to zero.

    (2x+5) (3x-2) = 0

    Having done this, you know that either (2x+5) = 0, or (3x-2)=0, as there are two factors in the equation, so if one of them is zero, it doesn't matter what the other one is, the product will be zero too.

    If 2x+5 = 0, then:

    2x = -5

    so: x = -5/2

    Alternatively, if: 3x-2 = 0,

    then: 3x = 2,

    x = 2/3

    So the two possible values for x are -5/2 and/or 2/3.

    Hope this helps

    G
    isn't my way right???
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    (Original post by Babygal)
    Hi this is what i got, check it with someone just in case im not right, but i think i am

    1. (2x+5) (3x-2)=0
    2. 6x^2-4x+15x=10
    3. 6x^2+12x=10
    4. factorise 6x(x+2)=10
    you can't solve 6x(x+2)=10 direcly.
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    (Original post by Babygal)
    isn't my way right???
    not really.
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    (Original post by elpaw)
    not really.
    So what is the right way? Now I am confused!
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    (Original post by elpaw)
    not really.

    lol true, my math needs sortin
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    Dont worry about the good old quadratic equations.
    It soon becomes clear.
    And unless you do engineering, you neva need them again.

    Free Spirit
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    (Original post by gemgems89)
    So what is the right way? Now I am confused!
    the way gztfan did it.
 
 
 
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