Many designs have half-turn symmetry, which is sometimes called point
symmetry. You can check for half-turn symmetry by turning the shape
upside down and seeing if it looks the same.
If it looks the same upside down and right side up, then it has half
turn symmetry.
Turn this parallelogram 180 (a half turn) to see if it has half-turn
symmetry
Try turning this rectangle upside down. Does it have half-turn
symmetry?
Try turning this rhombus upside down to check if it has half-turn
symmetry
Try turning this trapezoid upside down. Does it have half-turn
symmetry?
This trapzoid sometimes fools your eye, because it has line symmetry,
but it doesn't have half-turn symmetry.
Try out each of these shapes. First imagine what would happen if you
turned them upside down. Then try it to check for half-turn symmetry.
Of the 7 shapes on this page, you should have found 5 that have
half-turn symmetry, and 2 that do not.
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