Select the correct answer.

Consider this quadratic equation:
[tex]\[ x^2 + 1 = 2x - 3 \][/tex]

Which expression correctly sets up the quadratic formula?

A. [tex]\(\frac{-(-2) \pm \sqrt{(-2)^2 - 4(1)(4)}}{2(1)}\)[/tex]

B. [tex]\(\frac{-(-2) \pm \sqrt{(-2)^2 - (1)(4)}}{2(2)}\)[/tex]

C. [tex]\(\frac{-2 \pm \sqrt{(-2)^2 - 4(1)(4)}}{2(1)}\)[/tex]

D. [tex]\(\frac{-2 \pm \sqrt{(2)^2 - 4(1)(-2)}}{2(1)}\)[/tex]



Answer :

Let's start by rearranging the given quadratic equation [tex]\( x^2 + 1 = 2x - 3 \)[/tex] into the standard form [tex]\( ax^2 + bx + c = 0 \)[/tex].

1. Start with the given equation:
[tex]\[ x^2 + 1 = 2x - 3 \][/tex]

2. Move all terms to one side to set the equation to [tex]\( 0 \)[/tex]:
[tex]\[ x^2 + 1 - 2x + 3 = 0 \][/tex]

3. Simplify the equation:
[tex]\[ x^2 - 2x + 4 = 0 \][/tex]

Now that the equation is in the standard quadratic form [tex]\( ax^2 + bx + c = 0 \)[/tex], we can identify the coefficients:
[tex]\[ a = 1, \quad b = -2, \quad c = 4 \][/tex]

Next, we use the quadratic formula to find the roots of the equation:
[tex]\[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \][/tex]

Substituting the coefficients [tex]\( a = 1 \)[/tex], [tex]\( b = -2 \)[/tex], and [tex]\( c = 4 \)[/tex] into the quadratic formula, we get:
[tex]\[ x = \frac{-(-2) \pm \sqrt{(-2)^2 - 4(1)(4)}}{2(1)} \][/tex]

Therefore, the correct expression is:
[tex]\[ \frac{-(-2) \pm \sqrt{(-2)^2 - 4(1)(4)}}{2(1)} \][/tex]

This matches option A. The correct setup for the quadratic formula is:

A. [tex]\(\frac{-(-2) \pm \sqrt{(-2)^2 - 4(1)(4)}}{2(1)}\)[/tex]