Can the square of an irrational number be rational?

Answer 1

The answer to this question confuses me. The square root of two is an irrational number, so obviously if the square root of two is squared it becomes two which is a rational number. Thinking of it that way then the answer is yes, the square of an irrational number can be a rational number. But . . .

You had to know beforehand that the irrational number was the square root of another number. If you start out with an irrational number such as Pi you cannot square it because you cannot know the entire number in order to square it.