Solve using the quadratic formula: x2 - 2x - 24 = 0

2023

Solve using the quadratic formula: x2 - 2x - 24 = 0

  1. A.

    A. x = -6; x = 4

  2. B.

    B. x = 4; x = 6

  3. C.

    C. x = 6; x = -4

  4. D.

    D. x = -4; x = -6

Attempted by 6 students.

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Correct answer: C

Step-by-Step Solution

To solve the quadratic equation x^2 - 2x - 24 = 0 using the quadratic formula, follow these steps:

  1. Identify the coefficients: The standard form of a quadratic equation is ax^2 + bx + c = 0. For your equation, a = 1, b = -2, and c = -24.

  2. Apply the quadratic formula: The quadratic formula is x = (-b +/- sqrt(b^2 - 4ac)) / (2a). Substitute the values: x = (-(-2) +/- sqrt((-2)^2 - 4 * 1 * -24)) / (2 * 1)

  3. Simplify the expression: x = (2 +/- sqrt(4 + 96)) / 2 x = (2 +/- sqrt(100)) / 2 x = (2 +/- 10) / 2

  4. Find the two roots:

    • Root 1: x = (2 + 10) / 2 = 12 / 2 = 6

    • Root 2: x = (2 - 10) / 2 = -8 / 2 = -4

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