Join IDNLearn.com and start exploring the answers to your most pressing questions. Our experts are available to provide accurate, comprehensive answers to help you make informed decisions about any topic or issue you encounter.

In simplest radical form, what are the solutions to the quadratic equation [tex]0 = -3x^2 - 4x + 5[/tex]?

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

A. [tex]x = -\frac{2 \pm \sqrt{19}}{3}[/tex]

B. [tex]x = -\frac{2 \pm 2\sqrt{19}}{3}[/tex]

C. [tex]x = \frac{2 \pm \sqrt{19}}{3}[/tex]

D. [tex]x = \frac{2 \pm 2\sqrt{19}}{3}[/tex]


Sagot :

To solve the quadratic equation [tex]\(0 = -3x^2 - 4x + 5\)[/tex] using the quadratic formula, we follow these steps:

1. Identify the coefficients: In the quadratic equation [tex]\(ax^2 + bx + c = 0\)[/tex], we have:
- [tex]\(a = -3\)[/tex]
- [tex]\(b = -4\)[/tex]
- [tex]\(c = 5\)[/tex]

2. Calculate the discriminant: The discriminant ([tex]\(\Delta\)[/tex]) is given by [tex]\(b^2 - 4ac\)[/tex]:
[tex]\[ \Delta = (-4)^2 - 4 \cdot (-3) \cdot 5 = 16 + 60 = 76 \][/tex]
The discriminant is 76.

3. Apply the quadratic formula: The quadratic formula is:
[tex]\[ x = \frac{-b \pm \sqrt{\Delta}}{2a} \][/tex]
Plugging in the values of [tex]\(a\)[/tex], [tex]\(b\)[/tex], and [tex]\(\Delta\)[/tex]:
[tex]\[ x = \frac{-(-4) \pm \sqrt{76}}{2 \cdot (-3)} = \frac{4 \pm \sqrt{76}}{-6} \][/tex]

4. Simplify the square root and the fraction: Firstly, we simplify [tex]\(\sqrt{76}\)[/tex]:
[tex]\[ \sqrt{76} = \sqrt{4 \cdot 19} = 2\sqrt{19} \][/tex]
Now, plug this back into the formula:
[tex]\[ x = \frac{4 \pm 2\sqrt{19}}{-6} \][/tex]

5. Simplify the expression: We can factor out a 2 from the numerator:
[tex]\[ x = \frac{2(2 \pm \sqrt{19})}{-6} = \frac{2 \pm \sqrt{19}}{-3} \][/tex]

Since the fraction has a negative denominator, we can rewrite it as:
[tex]\[ x = -\frac{2 \pm \sqrt{19}}{3} \][/tex]

Hence, the solutions to the quadratic equation [tex]\(0 = -3x^2 - 4x + 5\)[/tex] in simplest radical form are:
[tex]\[ x = -\frac{2 + \sqrt{19}}{3} \quad \text{and} \quad x = -\frac{2 - \sqrt{19}}{3} \][/tex]

So the correct answer is:
[tex]\[ x = -\frac{2 \pm \sqrt{19}}{3} \][/tex]