X+2y+4z=31
5x+y+2z=29
3x–y+z=10
|1 2 4|
|5 1 2|=1–20+12–12+2–10=–27
|3 –1 1|
Δx=
|31 2 4|
|29 1 2| =31–116+40–40+62–58=–81
|10 –1 1|
Δy=
|1 31 4|
|5 29 2| =29+200+186–348–20–155=–108
|3 10 1|
Δz=
|1 2 31|
|5 1 29| = 10–155+174–93+29–100=–135
|3 –1 10|
x=( Δx)/ Δ=(–81)/(–27)=3,
y=( Δy)/ Δ=(–108_/(–27)=4,
z=( Δz)/ Δ=(–135_/(–27)=5.
Ответ: (3; 4; 5).