factor 16 and see the - factor pairs and add them, see which add to -12
-1-16=-17 nope
-2-8=-10 nope
-4-4=-8
hmm
we will solve with math
xy=16
x+y=-12
minus x both sides
y=-12-x
sub for y in other equation
x(-12-x)=16
-12x-x^2=16
add 12x+x^2 both sides
0=x^2+12x+16
use quadratic formula
if you have
ax^2+bx+c=0
x=[tex] \frac{-b+/- \sqrt{b^{2}-4ac} }{2a} [/tex]
0=x^2+12x+16
a=1
b=12
c=16
x=[tex] \frac{-12+/- \sqrt{12^{2}-4(1)(16) }}{2(1)} [/tex]
x=[tex] \frac{-12+/- \sqrt{144-64 }}{2} [/tex]
x=[tex] \frac{-12+/- \sqrt{80}}{2} [/tex]
x=[tex] \frac{-12+/- 4\sqrt{5}}{2} [/tex]
x=[tex] \frac{-6+/- 2\sqrt{5} [/tex]
x=[tex] \frac{-6+ 2\sqrt{5} [/tex] or [tex] \frac{-6- 2\sqrt{5} [/tex]
aprox
x=-1.52786 or -10.4721
those are the numbers
the numbes are -1.52786 or -10.4721
