Question

 rezolvati sistemul de ecuatii: $\left \{ {{x+y=5} \atop {xy=6}} \right.$

Answer 1

x=6/y
inlocuim in x+y=5
6/y+y=5
(6+y²)/y=5
6+y²=5y
y²-5y+6=0
Δ=25-24=1
y₁=(5-1)/2=2
y₁=2
y₂=(5+1)/2=3
y₂=3
x₁=6/y₁=6/2=3
x₁=3
x₂=6/y₂=6/3=2
x₂=2

deci : x₁=3 si y₁=2
          x₂=2 si y₂=3