How do you solve $x^{2} + 5 x + 4 = 0$ $x^2 + 5x + 4 = 0$ ?

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Answer 1 · 2017-07-25T05:20:13

You would factorise the equation first into this form
$(x + k) (x + r) = 0$ $(x+k)(x+r) = 0$

To do this you ask yourself this

What times what equals to 4
$k \cdot r = 4$ $k*r=4$

And what adds together to get 5
$k + r = 5$ $k + r=5$

$k = 1$ $k=1$
$r = 4$ $r=4$

$(x + 1) (x + 4) = 0$ $(x + 1)(x + 4) = 0$

$x = - 1$ $x = -1$
$x = - 4$ $x = -4$

How do you solve x^2 + 5x + 4 = 0 x2+5x+4=0x^2 + 5x + 4 = 0 ?