Question

Which statement is logically equivalent to the following conditional statement?

If it is a rectangle, then it does not have three sides.

If it has three sides, then it is not a rectangle.

If it is not a rectangle, then it has three sides.

If it does not have three sides, then it is a rectangle.

If it is not a rectangle, then it does not have three sides.

Answer 1

B cannot be, as if it's not a rectangle, it can still have other numbers of sides than three. Similarly, C cannot b, since if it does not have 3 sides, it may not be a rectangle. The last one is false by similar reasons. Therefore, I would say A would a remark.

Answer 2

Thank you!

Answer 3

The remark is that if you have a statement p that implies q, q does not necessarily implies p. It just so happen that if the figure has 3 sides, it cannot be a rectangle. But that shouldn't be generalized. Also, wait for a second opinion, as I may be commiting a logical mistake here. :-) And you are welcome, so far.