solve. (x+4)(x-18)(x+2 0

Question

solve. (x+4)(x-18)(x+2 >0

hero · Answer

Saifoo, help him

anonymous · Answer

(x + 4 )(x - 18) (x +2)> 0 

Draw a Number Line 

<------------------------------------------|------------------------|--------------------------------|-------------------->
$-\infty$                                          -4                             -2                                         18                       $\infty$

anonymous · Answer

Now, check the intervals in which the function is greater than zero 
$- - - - -$                                         $ +++  $                         $- - - - $                           $+++$
<------------------------------------------|------------------------|--------------------------------|-------------------->
$-\infty$                                           -4                               -2                                         18                       $\infty$

anonymous · Answer

which make the solution 
$$x \in (-4,-2)\cup(18,\infty)$$