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Help with quadratic equations please :D?

How would I solve these, I have to solve each by graphing./

m^2+3m=28

3 Answers

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  • TomV
    Lv 7
    1 decade ago
    Favorite Answer

    Draw a graph of the function y = x² + 3x - 28

    Where the graph crosses the x axis, the x-intercepts, are the zeros of the function, or the values which satisfy the relation m² +3m = 28

    since m²+3m-28 can be factored to (m+7)(m-4), the intercepts, zeros, or solutions will be -7 and 4.

  • Anonymous
    1 decade ago

    First move over the 28 to the left side of the equation.

    m^2+3m-28=0.

    Then factor.

    (m+7)(m-4)=0

    Why did I pick 7 and -4?

    Because 7 times -4 = -28.

    7+(-4) = 3.

    If you multiple (m+7)(m-4) this out, you will get m^2+3m-28 which is what we want b/c the two equations are equal.

    Now just solve them independently.

    m+7 = 0

    m-4 = 0

    m= -7, 4

    :)

  • Anonymous
    1 decade ago

    m=3

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