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Find the roots of 3x^(2) - 5x - 12 = 0....

Find the roots of `3x^(2) - 5x - 12 = 0`.

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To find the roots of the quadratic equation \(3x^2 - 5x - 12 = 0\), we can follow these steps: ### Step 1: Identify coefficients The given quadratic equation is in the standard form \(ax^2 + bx + c = 0\). Here, we identify: - \(a = 3\) - \(b = -5\) - \(c = -12\) ### Step 2: Apply the quadratic formula The quadratic formula to find the roots is given by: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] ### Step 3: Substitute the values into the formula Substituting the values of \(a\), \(b\), and \(c\) into the formula: \[ x = \frac{-(-5) \pm \sqrt{(-5)^2 - 4 \cdot 3 \cdot (-12)}}{2 \cdot 3} \] ### Step 4: Simplify the expression Calculating the components: - The term \(-(-5)\) becomes \(5\). - The term \((-5)^2\) is \(25\). - The term \(4 \cdot 3 \cdot (-12)\) is \(-144\), so \(b^2 - 4ac\) becomes: \[ 25 - (-144) = 25 + 144 = 169 \] Now substituting back into the equation: \[ x = \frac{5 \pm \sqrt{169}}{6} \] ### Step 5: Calculate the square root Since \(169\) is a perfect square, we have: \[ \sqrt{169} = 13 \] Thus, the equation now becomes: \[ x = \frac{5 \pm 13}{6} \] ### Step 6: Calculate the two possible values for \(x\) Now we can find the two roots: 1. For \(x = \frac{5 + 13}{6}\): \[ x = \frac{18}{6} = 3 \] 2. For \(x = \frac{5 - 13}{6}\): \[ x = \frac{-8}{6} = -\frac{4}{3} \] ### Conclusion The roots of the equation \(3x^2 - 5x - 12 = 0\) are: \[ x = 3 \quad \text{and} \quad x = -\frac{4}{3} \] ---
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