## Algebra and Trigonometry 10th Edition

$Discriminant\gt0$: two real solutions. $Discriminant=0$: one real solution. $Discriminant\lt0$: no real solutions. $x^2+2x+4=0~~$ ($a=1,b=2,c=4$) $Discriminant=b^2-4ac=2^2-4(1)(4)=4-16=-12$