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    ok so i got x=-2

    what do i do with the 3x? or is there only one solution?

    when i come across equations looking like that with one set of brackets i get confused
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    Presumably you got x = -2 because this is the value that makes (x + 2) equal to zero.

    If you think of the equation as (3x)(x - 2) = 0, you have found the value of x that makes the second bracket equal to zero.

    Now - what is the value of x that makes the first bracket equal to zero?
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    The second solution is x = 0. If 3x(x+2) = 0, then either x+2=0 or 3x=0; the only way two things multiplied together can equal zero is if one of them is zero.

    (Original post by ihatePE)
    ok so i got x=-2

    what do i do with the 3x? or is there only one solution?

    when i come across equations looking like that with one set of brackets i get confused
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    -2 and 0

    Equations looking like that always have at least one answer as 0
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    x=0.
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    if you draw a graph of y = 3x( x + 2 ) you will see that it crosses the x axis at two points.
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    (Original post by Pangol)
    Presumably you got x = -2 because this is the value that makes (x + 2) equal to zero.

    If you think of the equation as (3x)(x - 2) = 0, you have found the value of x that makes the second bracket equal to zero.

    Now - what is the value of x that makes the first bracket equal to zero?
    (Original post by Jasaron)
    The second solution is x = 0. If 3x(x+2) = 0, then either x+2=0 or 3x=0; the only way two things multiplied together can equal zero is if one of them is zero.
    of course, thanks, <3
 
 
 
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