Which of the following sets are subspaces of R? O A. {(-2, y, z) | y, z arbitrary numbers } ) B. {(x, Y, z) | x + y + z = –5} OC. {(x, Y, z) | 2x – 6y = 0, 9x + 5z = 0} OD. {(5x + 4y, 8x + 7y, – 3x –...

Extracted text: Which of the following sets are subspaces of R? O A. {(-2, y, z) | y, z arbitrary numbers } ) B. {(x, Y, z) | x + y + z = –5} OC. {(x, Y, z) | 2x – 6y = 0, 9x + 5z = 0} OD. {(5x + 4y, 8x + 7y, – 3x – 7y) | x, y arbitrary numbers } ) E. {(x, y, z) | x, y, z > 0} F {(x, Y, z) | – 2x + 6y – 9z = 0}