Question
Consider the vectors x = i +2 j +3 k , y =2 i +3 j + k , and z =3 i + j +2 k For two distinct positive real numbers and , define X = x + y - z , Y = y + z - x , and Z = z + x - y If the vectors X , Y , and Z lie in a plane, the value of + -3 is ______ .