Метод крамера. {5x+3y+z=4 {6x+5y+z=5 {7x+8y+z=6

    Ι531Ι
Δ=Ι651Ι= 5*5*1+1*6*8+3*1*7-1*5*7-3*6*1-5*1*8=25+48+21-35-18-40=1
    Ι781Ι
    
      Ι431Ι
Δ1=Ι551Ι=4*5*1+1*5*8+3*1*6-1*5*6-4*1*8-3*5*1=20+40+18-30-32-15=1
      Ι681Ι
      
      Ι541Ι
Δ2=Ι651Ι=5*5*1+1*6*6+4*1*7-1*5*7-5*1*6-4*6*1=25+36+28-35-30-24=0
      Ι761Ι
  
      Ι534Ι
Δ3=Ι655Ι=5*5*6+4*6*8+3*5*7-4*5*7-5*5*8-3*6*6=150+192+105-140-200-108=-1
      Ι786Ι

х1=Δ1/Δ=1/1=1
х2=Δ2/Δ=0/1=0
х3=Δ3/Δ=1/-1=-1