Worked Example 1
Find the lines of symmetry and the order of rotational symmetry of a rectangle.
Try foldingTwo folds work: the vertical line and the horizontal line through the middle.
Now try the diagonals2 lines of symmetry. The diagonals look promising but fail the fold test.
Now turn itOrder 2. A 180 degree turn works, a 90 degree turn does not.
Worked Example 2
A shape has rotational symmetry of order 6. What is the smallest angle you can turn it through?
What order meansThe 6 positions are evenly spaced round the full 360 degrees.
Divide60 degrees, and it also works at 120, 180, 240, 300 and 360.
Read the question carefullyOrder is a count with no unit; angle is in degrees. Writing 6 degrees or order 60 loses the mark.
1 more worked examples - sign in to see them all.