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Help w/ algebra 3/4?!?

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how do you solve this equation: xSquared + x - 12 = 0

i have a couple equations in that form, and i just need help with that one to get me started. thank you:]

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  1. x^2 + x - 12 = 0

    You factor.

    (x-3)(x+4) = 0

    x = 3, -4

    Check answers.

    3^2 + 3 - 12 = 0

    9+3 - 12 = 0

    True

    -4^2 - 4 - 12 = 0

    16 - 4 - 12 = 0

    True






  2. Pranil  answered this 3 months ago and got best answer

    in the mathematics section

    Best Answer - Chosen by Voters

    x² + x – 12

    find the factors of 12 such thet their sum or difference is 1

    3 × 4 = 12 and 4 – 3 = 1

    x² + x – 12

    = x² + 4x – 3x – 12

    = x(x + 4) – 3(x + 4)

    = (x – 3)(x + 4)

    x = 3 or x = – 4

    ---------

  3. It is a quadratic equation, you need to factor it and get it in the form

    (x-A)(x-B)=0, so the answer will then be, x=A and x=B

    For that example

    (x+4)(x-3)=0, so x=-4 and x=-3 is your answer.

    If you write your equation in this form:

    Dx(squared) + Ex + F =0

    then you need (x-A)(x-B)=0,

    where A+B=E and AB=F

    use that trick and you should always be able to factor the formula and get the answer..

    The trick is that, A+B

  4. I would factor it (or you can use quadratic formula).

    (x + 4) (x - 3) = 0 .....I found factors of 12 that had a difference of 1

    Set each factor equal to zero (zero product property)

    x + 4 = 0 or x - 3 = 0

    x = -4 or x = 3

    Hope this helps !

  5. factor the top one

    x^2 + x - 12 = 0

    (x + 4) (x - 3) = 0

    which means x = -4, x = 3

    2sqrt(32) = 8sqrt(2)

    6sqrt (8)  = 12 sqrt (2)

    sqrt 128  = 8 sqrt (2)

    all of these have perfect squares that can be taken out from the radical

    so it would be 8sqrt(2) + 12 sqrt(2) - 8sqrt(2)

    = 12 sqrt (2)

  6. (x+4)(x-3)

    x=-4   x=3

    8radical2+12radical2-8radical2=

    12radical2
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