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True or False ? Please Justify/ Explain you answer . 10 points best answer?

Is (X +2)^3 = x^3 -4 a quadratic equation .

6 Answers

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  • 7 years ago

    (generally) there are 3 types of statements.

    1)  TRUE statement

    2)  FALSE statement

    3)  OPEN statement

    For example, a FALSE statement would be

             x + 1 = x - 4

    because you know that it is FALSE for any

    value of x, since when you subtract x from

    both sides you a statement    " 1 = -4 "

    and thus you know that it is for sure FALSE.

    A TRUE statement would, for example be,

             g² + 3 = g² + 3

    since you see that what is basically says is,

    " a number = a number ", and you know that

    it is true, just like  1=1  r=r   3=3  -6=-6

    and on...   is true, (right?)

    In other words, whatever number you plug in

    for g  into      g² + 3 = g² + 3,   the sides will

    always be equal to each other.

    An OPEN statement however, would be something like,

            w + 3 = 2w - 1

    Here, you get a statement that is OPEN,

    because you can solve the equation and

    find what "w" equals.

    Solution:

            w + 3 = 2w - 1      

       add 1 to both sides

            w + 3 = 2w - 1      

                + 1         + 1

          ───────────

            w + 4 = 2w

    (the 1 on the right side has canceled)

    Now, subtract w from both sides

            w + 4 = 2w      

          - w         - w

          ───────────

             4 = w

    and hence, you know that

            w + 3 = 2w - 1      

    is true when  w  is 4

    but false for any other values.

    This statement, that can be solved for the variable

    to find what the variable equals (to make the statement true)

    is called an OPEN statement.

    Source(s): ▒ No sources ▒
  • 7 years ago

    You're not making much sense. Statements are true or false. Questions are not true or false.

    "Is (X +2)^3 = x^3 -4 a quadratic equation?" is a question not a statement. Therefore it makes no sense to ask if it is true or false.

    (X +2)^3 = x^3 -4 is a quadratic equation because it can be written in the form ax^2+bx+c = 0.

  • 6 years ago

    no

    (x + 2)^3 = (x + 2)(x + 2)(x + 2)

    = (x + 2)(x^2 + 4x + 4)

    = x^3 + 6x^2 + 12x + 8

    in general this is not the same as x^3 - 4

    therefore false

  • Glipp
    Lv 7
    7 years ago

    no

    (x + 2)^3 = (x + 2)(x + 2)(x + 2)

    = (x + 2)(x^2 + 4x + 4)

    = x^3 + 6x^2 + 12x + 8

    in general this is not the same as x^3 - 4

    it may be the same if 6x^2 + 12x + 8 = -4

    or 6x^2 + 12x + 12 = 0

    => x^2 + 2x + 2 = 0

    => (x + 1)^2 = -1

    => x + 1 = ±i

    => x = -1 ± i

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  • DWRead
    Lv 7
    7 years ago

    (x+2)² = x³-4

    x²+4x+4 = x³-4

    x³-x²-4x-8 = 0

    This is a cubic equation.

  • 7 years ago

    Drop the course

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