Respuesta :

Answer:

x=-1 and x=5

Step-by-step explanation:

we have

[tex]x^{2} -4x=5[/tex]

Solve it by completing the square method

We take the coefficient of x that is -4, divide it by 2 and then square it

so

[tex]-\frac{4}{2}=-2[/tex]

square it

[tex](-2)^2 = 4[/tex]

Adds 4 both sides

[tex]x^{2} -4x+4=5+4[/tex]

Combine like terms right side

[tex]x^{2} -4x+4=9[/tex]

Rewrite as perfect squares

[tex](x-2)^{2}=9[/tex]

take square root both sides

[tex]x-2=\pm3[/tex]

[tex]x=2\pm3[/tex]

therefore

[tex]x=2+3=5[/tex]

[tex]x=2-3=-1[/tex]