The set of the all values of `lamda` for which the system of linear equations
`2x_(1) - 2x_(2) + x_(3) = lamdax_(1)`
`2x_(1) - 3x_(2) + 2x_(3) = lamda x_(2)`
`-x_(1) + 2x_(2) = lamda x_(3)` has a non-trivial solution,
A. contains two elements
B. contains more than two elements
C. is an empty set
D. is a singleton
