Solve for x in the equation x squared + 2 x + 1 = 17.
x = negative 1 plus-or-minus StartRoot 15 EndRoot
x = negative 1 plus-or-minus StartRoot 17 EndRoot
x = negative 2 plus-or-minus 2 StartRoot 5 EndRoot
x = negative 1 plus-or-minus StartRoot 13 EndRoot

Answer :

Answer:

The answer to your question is the second option

Step-by-step explanation:

Process

1.- Write the equation

                                 x² + 2x + 1 = 17

Factor the first term

                                 (x + 1)² = 17

Get the square root

                                 [tex]\sqrt{(x+1)^{2} }  = \sqrt{17}[/tex]

                                 (x + 1) = [tex]\sqrt{17}[/tex]

Result

                                x₁ = - 1 + [tex]\sqrt{17}[/tex]

                                 x₂ = -1  - [tex]\sqrt{17}[/tex]                                

                               

                                 

Answer:

Option B.

Step-by-step explanation:

The given equation is

[tex]x^2+2x+1=17[/tex]

Subtract both sides by 17.

[tex]x^2+2x+1-17=17-17[/tex]

[tex]x^2+2x-16=0[/tex]          .... (1)

If a quadratic equation is [tex]ax^2+bx+c=0[/tex], then by quadratic formula

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

In equation (1), a=1, b=2 and c=-16. Using quadratic formula we get

[tex]x=\dfrac{-(2)\pm \sqrt{(2)^2-4(1)(-16)}}{2(1)}[/tex]

[tex]x=\dfrac{-2\pm \sqrt{4+64}}{2}[/tex]

[tex]x=\dfrac{-2\pm \sqrt{68}}{2}[/tex]

[tex]x=\dfrac{-2\pm 2\sqrt{17}}{2}[/tex]

Taking out common factors.

[tex]x=\dfrac{2(-1\pm \sqrt{17})}{2}[/tex]

[tex]x=-1\pm \sqrt{17}[/tex]

Therefore, the correct option is B.

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