Select the correct answer.

What are the solutions of this equation?
[tex]\[ 3x^2 - 5x - 13 = 0 \][/tex]

A. [tex]\[ x = \frac{5 \pm \sqrt{131}}{6} \][/tex]

B. [tex]\[ x = \frac{5 \pm \sqrt{181}}{6} \][/tex]

C. [tex]\[ x = \frac{-5 \pm \sqrt{181}}{6} \][/tex]

D. [tex]\[ x = \frac{-5 \pm \sqrt{131}}{6} \][/tex]



Answer :

To solve the quadratic equation [tex]\(3x^2 - 5x - 13 = 0\)[/tex], we will use the quadratic formula. The quadratic formula is given by:

[tex]\[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \][/tex]

where [tex]\(a\)[/tex], [tex]\(b\)[/tex], and [tex]\(c\)[/tex] are the coefficients from the quadratic equation [tex]\(ax^2 + bx + c = 0\)[/tex].

For our equation [tex]\(3x^2 - 5x - 13 = 0\)[/tex]:
- [tex]\(a = 3\)[/tex]
- [tex]\(b = -5\)[/tex]
- [tex]\(c = -13\)[/tex]

Let's start by substituting these values into the quadratic formula.

First, calculate the discriminant:

[tex]\[ \Delta = b^2 - 4ac \][/tex]

Substitute the coefficients into the discriminant formula:

[tex]\[ \Delta = (-5)^2 - 4(3)(-13) \][/tex]

Evaluate the terms:

[tex]\[ \Delta = 25 + 156 \][/tex]

[tex]\[ \Delta = 181 \][/tex]

Now that we have the discriminant, we can substitute back into the quadratic formula:

[tex]\[ x = \frac{-b \pm \sqrt{\Delta}}{2a} \][/tex]

Substitute [tex]\(b = -5\)[/tex], [tex]\(\Delta = 181\)[/tex], and [tex]\(a = 3\)[/tex]:

[tex]\[ x = \frac{-(-5) \pm \sqrt{181}}{2(3)} \][/tex]

Simplify:

[tex]\[ x = \frac{5 \pm \sqrt{181}}{6} \][/tex]

Therefore, the solutions to the equation [tex]\(3x^2 - 5x - 13 = 0\)[/tex] are:

[tex]\[ x = \frac{5 \pm \sqrt{181}}{6} \][/tex]

Hence, the correct answer is:

[tex]\[ \boxed{\frac{5 \pm \sqrt{181}}{6}} \][/tex]