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Can You Show Me Step By Step How To Solve 2x^2-3x-2=0 In Quadratic Formula?

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    The quadratic formula gives the solution to
    ax2+bx+c = 0

    as
    x = (-b ±√(b2-4ac))/(2a)    (this is "the quadratic formula")

    You have
    2x2 -3x -2 = 0

    So a=2, b=-3, c=-2.
    We substitute these values into the quadratic formula.
    x = (-b ±√(b2-4(2)c))/(2(2))    (we have put (2) where a was)
    x = (-(-3) ±√((-3)2-4(2)c))/(2(2))    (we have put (-3) where b was)
    x = (-(-3) ±√((-3)2-4(2)(-2)))/(2(2))    (we have put (-2) where c was)

    Now, we evaluate according to the order of operations.
    First, we evaluate parentheses. ((-3)2-4(2)(-2))
    Within that, we evaluate exponents. (-3)2 = 9, so the parentheses enclose (9 -4(2)(-2))
    Then, we multiply (9 -8(-2)), (9 + 16)
    Then, we add (25).

    Now, we have
    x = (-(-3) ±√(25))/(2(2))

    Next, we do the root. √25 = 5
    Now, we have

    x = (-(-3) ±5)/(2(2))


    Next, we do the multiplication inside each of the parentheses.
    x = (3 ±5)/4

    Now, parentheses again
    x = 8/4    (when we use the + sign)
    x = -2/4    (when we use the - sign)

    Finally, we can perform the division
    x = 2
    x = -1/2

    This is your solution.
    1 0

    Oddman  

    answered 10 months ago

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