X(y+z)=2, y(x+z)=-28, z(x+y)=-10. Найдите x,y,z.
Xy+zx =2 yx+yz= -28 zx+yz = -10 xy = 2-zx 2-xz + yz = -28 -> xz = 30 + yz 30+yz + yz = -10 -> yz = -20 -> xz = 10 -> xy = -8 yz/xz = -2 и xy = -8 -> y = -+4 , x = +-2 -> z = +-5