What are the solutions to the equation shown?

[tex] x^2 - 5x - 1 = 0 [/tex]

A. [tex] x = \frac{5 \pm \sqrt{6}}{2} [/tex]

B. [tex] x = \frac{5 \pm \sqrt{14}}{2} [/tex]

C. [tex] x = \frac{5 \pm \sqrt{21}}{2} [/tex]

D. [tex] x = \frac{5 \pm \sqrt{29}}{2} [/tex]



Answer :

First, let's identify the coefficients of the quadratic equation [tex]\( x^2 - 5x - 1 = 0 \)[/tex]. Here, [tex]\( a = 1 \)[/tex], [tex]\( b = -5 \)[/tex], and [tex]\( c = -1 \)[/tex].

The general form for solving a quadratic equation [tex]\( ax^2 + bx + c = 0 \)[/tex] is given by the quadratic formula:

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

Let's go through the steps to find the discriminant:

[tex]\[ \text{discriminant} = b^2 - 4ac \][/tex]

Substitute [tex]\( a \)[/tex], [tex]\( b \)[/tex], and [tex]\( c \)[/tex]:

[tex]\[ \text{discriminant} = (-5)^2 - 4(1)(-1) = 25 + 4 = 29 \][/tex]

Now, substitute [tex]\( b = -5 \)[/tex], the discriminant, and [tex]\( a = 1 \)[/tex] into the quadratic formula:

[tex]\[ x = \frac{-(-5) \pm \sqrt{29}}{2(1)} = \frac{5 \pm \sqrt{29}}{2} \][/tex]

Thus, the solutions to the quadratic equation [tex]\( x^2 - 5x - 1 = 0 \)[/tex] are:

[tex]\[ x = \frac{5 + \sqrt{29}}{2} \quad \text{and} \quad x = \frac{5 - \sqrt{29}}{2} \][/tex]

Comparing this with the options provided, we find that the correct answer is:

D. [tex]\( x = \frac{5 \pm \sqrt{29}}{2} \)[/tex]