Step by step
The question
Question: how many lines of symmetry does a parallelogram have?
1 Try the folds
Imagine folding the shape along a line.
If the two halves match exactly, it is a line of symmetry.
Fold straight down the middle.
The corners do not meet.
It is not a line of symmetry.
Fold across the middle.
The corners do not meet.
It is not a line of symmetry.
Fold along a diagonal.
The corners do not meet.
It is not a line of symmetry.
2 Count the lines
No fold works.
So a parallelogram has 0 lines of symmetry.
lines of symmetry = 0
Careful!
A parallelogram leans.
Folding it down the middle or across the middle does not work.
Careful: not 2 ✗
Let's look back.
First: try the folds.
Last: count the lines.
Answer
lines of symmetry = 0