{2x-y-3z=6
x+y+2z=1
3x+2y+2z=2
A=2 -1 -3
1 1 2
3 2 2
calculam determinantul acestei matrice
Δ=4-6-6+9-8+2
Δ=5 diferit de 0 deci sistemul are solutii
Δx= 6 -1 -3
1 1 2
2 2 2
Δx=12-6-4+6-24+2
Δx=-14
Δy= 2 6 -3
1 1 2
3 2 2
Δy= 4-6+18+9-8-12
Δy=5
Δz=2 -1 6
1 1 1
3 2 2
Δz=4+12-3-18-4+2
Δz=-7
x=Δx/Δ=-14/5
y=Δy/Δ=5/5=1
z=Δz/Δ=-7/5
