The $3$ by $3$ grid has $4$ lines of symmetry.
How might this help?
Flips or Turns / Reflections-- are they the same or
different?
Try shading $1$ square only. What symmetries are possible?
Try shading $2, 3, 4 \ldots$ squares only. What symmetries are now
possible?
How helpful would this table be?
|
Lines of symmetry
|
||||||
|
0
|
1
|
2
|
3
|
4
|
||
|
Shaded |
1
|
|||||
|
2
|
||||||
|
3
|
||||||
|
4
|
||||||
What omissions do you notice?