How do you solve by completing the square $x^2 - 4x - 1 = 0$ ?

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Answer 1 · 2015-03-30T12:21:08

The roots are 2+ $sqrt5$ ; 2- $sqrt5$

Rewrite it as x^2 -4x +4-4-1=0
x^2 -4x+4=5
(x-2)^2 =5
x-2= + $sqrt5$ ; - $sqrt$ 5
x= 2 + $sqrt5$ ; 2- $sqrt5$

How do you solve by completing the square x^2 - 4x - 1 = 0x^2 - 4x - 1 = 0?