Keegan says that a quadrilateral is a square if and only if it is a rectangle. is this a true biconditional statement? a) yes, because all squares are rectangles. b) no, because all squares are not rectangles. c) yes, because all rectangles are squares. d) no, because all rectangles are not squares.

That would be a  
Every square  is also a rectangle.

E  none of the above
     not all   rectangles   are squares.

a) Yes, because all squares are rectangles.
true  but the statement   says  that  all   rectangles  are squares
A quadrilateral could be a rectangle and not a square

b) No, because all squares are not rectangles.
No    Not all rectangles are   squares  all   squares are   rectangles

c) Yes, because all rectangles are squares.
Nope    some   rectangles are  not squares

d) No, because all rectangles are not squares.
nope   some   rectangles are   squares.