Related Post: X 2 3 X1 3 2 0 ( X 1 2 3 )( X 2 3 = 0 X 2 3 3x 1 3 10 0 X 2 3 3x 1 3 4 0 ( X 1 - 2 - 3 )( X 2 - 3 ≥ 0 X/-2=3