Question 430837
x^2+8x+15>=0

{{{(x^2+5x+3x+15)>=0}}}
{{{(x(x+5)+3(x+5))>=0}}}
{{{((x+5)(x+3))>=0}}}

Either x+5>=0

{{{x>-5}}}
{{{(x+3)>=0}}}
{{{(x)>=-3}}}