Question

Solve the following quadratic equation by fatorization method: $x^2+9x+8=0$

Answer 1

$x^2+9x+8=0$
$\Rightarrow$ $x^2+8x+x+8=0$
$\Rightarrow$ $x(x+8)+1(x+8)=0$
$\Rightarrow$ $(x+8)(x+1)=0$
$\therefore$ $x+8=0$ $\Rightarrow$ $x=-8$
$\therefore$ $x+1=0$ $\Rightarrow$ $x=-1$