How do you solve $x^2 - 4x - 5 = 0$ by completing the square?

Question

1400 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2018-05-31T00:56:34

Below

$x^2-4x-5=0$

$x^2-4x=5$

$x^2-4x+(4/2)^2=5+(4/2)^2$

$x^2-4x+4 = 5+4$

$(x-2)^2=9$

$x-2=+-3$

$x-2=3$ OR $x-2=-3$

$x-2=3$
$x=5$

$x-2=-3$
$x=-1$

How do you solve x^2 - 4x - 5 = 0x^2 - 4x - 5 = 0 by completing the square?