How do you solve $x^2 -4x -5=0$ ?

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Answer 1 · 2015-06-28T07:37:52

The solutions are
$color(blue)(x=5, x=-1$

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

We can first factorise this expression by splitting the middle term and then find the solutions:

$x^2 color(blue)(-5x +1x)-5=0$

$x( x - 5) + 1 (x-5)=0$
$=color(blue)((x-5)(x+1)$

Equating the factors with zero to obtain the solutions:

How do you solve x^2 -4x -5=0x^2 -4x -5=0?