Respuesta :

Answer:

x = - 2 -[tex]\sqrt{15\\[/tex]

x = - 2 + [tex]\sqrt{15[/tex]

Step-by-step explanation:

The given equation needs to be solved by completing the squares.

The required values are -2+√15, -2-√15

Completing the squares

The given equation is [tex]x^2+4x-11=0[/tex]

The general form of a quadratic equaiton is [tex]ax^2+bx+c=0[/tex]

Comparing with the given equation we have

a = 1

b = 4

c = -11

Rearranging the equation

[tex]x^2+4x=11[/tex]

Finding (b/2)²

[tex](\dfrac{4}{2})^2=4[/tex]

Adding to both sides of the equation

[tex]x^2+4x+4=11+4\\\Rightarrow (x+2)^2=15\\\Rightarrow x+2=\pm\sqrt{15}\\\Rightarrow x=-2+\sqrt{15},-2-\sqrt{15}[/tex]

Learn more about completing the squares:

https://brainly.com/question/24860429