by tommywallach Wed Apr 16, 2014 8:52 pm
Hey Yi,
You should look at the definitions of these terms.
A rectangle: Any figure with four straight sides and four right angles. (See how a square would fit that definition?)
A square: A figure with four equal straight sides and four right angles. (See how not ALL rectangles would fit that definition?)
All of the other shapes you described have rules that would eliminate a square from consideration (they don't have four right angles).
Hope that helps!
-t