Answer:
-6+3[tex]\sqrt{2}[/tex] and -6-3[tex]\sqrt{2}[/tex]
Step-by-step explanation:
xy = 18
x+y = -12
y = -12-x
substitution method:
x(-12-x) = 18
-12x - x² - 18 = 0
-x² - 12x - 18 = 0
-(x² + 12x + 18) = 0
used quadratic formula:
(-12±√144 - 4(18)) ÷ 2
(-12 ± [tex]\sqrt{72}[/tex]) ÷ 2
(-12 ± 6[tex]\sqrt{2}[/tex]) ÷ 2
= -6 ± 3[tex]\sqrt{2}[/tex]
