$x^2+11x+18$ = 0

D = ${\left(\frac{11}{2}\right)}^2-18$ = $\frac{121}{4}$ $-$ $18$ = $\frac{121}{4}$$-$ $\frac{72}{4}$ = $\frac{49}{4}$

x_1,2 = $-\frac{11}{2}$ ± $\sqrt{\frac{49}{4}}$

x₁ = $-\frac{11}{2}$ - $\frac{7}{2}$ = $-\frac{18}{2}$ = -9

x₂ = $-\frac{11}{2}$ + $\frac{7}{2}$ = $-\frac{4}{2}$ = -2

L = { $-9$; $-2$}

$36+12x+x^2$ = 0

sortieren

$x^2+12x+36$ = 0

D = $6^2-36$ = $36$ $-$ $36$ = $0$

Da die Diskriminante D = 0 ist, hat die quadratische Gleichung nur eine Lösunng.

x = $-6$ - 0 = $-6$

L ={ $-6$}