Solve for [tex]\( x \)[/tex]. Round your answers to two decimal places.

[tex]\[ 2x^2 + 6x = 4 \][/tex]

A. [tex]\( x = -0.56 \)[/tex] and [tex]\( x = 3.56 \)[/tex]
B. [tex]\( x = 0.56 \)[/tex] and [tex]\( x = -3.56 \)[/tex]
C. [tex]\( x = -0.40 \)[/tex] and [tex]\( x = 2.90 \)[/tex]
D. [tex]\( x = 0.40 \)[/tex] and [tex]\( x = -2.90 \)[/tex]



Answer :

To solve the quadratic equation [tex]\( 2x^2 + 6x = 4 \)[/tex], we need to follow these steps:

1. Rearrange the equation to standard form:
The standard form of a quadratic equation is [tex]\( ax^2 + bx + c = 0 \)[/tex]. Start by moving all the terms to one side of the equation:
[tex]\[ 2x^2 + 6x - 4 = 0 \][/tex]

2. Identify the coefficients:
From the equation [tex]\( 2x^2 + 6x - 4 = 0 \)[/tex], we observe that:
[tex]\( a = 2 \)[/tex],
[tex]\( b = 6 \)[/tex], and
[tex]\( c = -4 \)[/tex].

3. Use the quadratic formula:
The quadratic formula is given by:
[tex]\[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \][/tex]

Substitute [tex]\( a = 2 \)[/tex], [tex]\( b = 6 \)[/tex], and [tex]\( c = -4 \)[/tex] into the formula:
[tex]\[ x = \frac{-6 \pm \sqrt{6^2 - 4 \cdot 2 \cdot (-4)}}{2 \cdot 2} \][/tex]
[tex]\[ x = \frac{-6 \pm \sqrt{36 + 32}}{4} \][/tex]
[tex]\[ x = \frac{-6 \pm \sqrt{68}}{4} \][/tex]
[tex]\[ x = \frac{-6 \pm \sqrt{4 \cdot 17}}{4} \][/tex]
[tex]\[ x = \frac{-6 \pm 2\sqrt{17}}{4} \][/tex]
Simplify the expression:
[tex]\[ x = \frac{-3 \pm \sqrt{17}}{2} \][/tex]

4. Calculate the solutions:
Now, we calculate the two possible solutions:
[tex]\[ x_1 = \frac{-3 + \sqrt{17}}{2} \][/tex]
[tex]\[ x_2 = \frac{-3 - \sqrt{17}}{2} \][/tex]

Evaluating these expressions, we find:
[tex]\[ x_1 \approx 0.56 \quad \text{(rounded to two decimal places)} \][/tex]
[tex]\[ x_2 \approx -3.56 \quad \text{(rounded to two decimal places)} \][/tex]

5. State the solutions:
Therefore, the solutions to the quadratic equation [tex]\( 2x^2 + 6x = 4 \)[/tex] are:
[tex]\[ x = 0.56 \quad \text{and} \quad x = -3.56 \][/tex]

Thus, the correct choice from the given options is:
[tex]\[x=0.56 \text{ and } x=-3.56\][/tex]