harjas2222
I did not quite understand the solution. To assume a= fraction is a far cry, as my mind went on to assume x either as perfect square or an imperfect one. Please specify theory and reason why a cannot be even?
The question asks which of the following
must be true. For this kind of question, if you can show that a statement is not true for even one valid value, then that statement is not always true and therefore cannot be the correct answer.
So the goal here is not to prove that the statements could be true. The goal is to show that they are not
necessarily true. Of course,
a could be even, positive, or an integer for some values of x. For example, if x = 4, then a = 4, which is all three. That is why the solution tries a value like x = 1/4, because it gives a = -1/8, which is not even, not positive, and not an integer. So none of the statements must be true.