If x < 5, then which of the following must be true?

-x < - 5

-x > - 5

-x < 5

-x > 5

If x > 5, than it stands to reason that - x 5, that is true, but when you add a negative in front of 17, it becomes - 17 > 5, which is not true, but - 17 < 5 is. The third answer choice is correct.