← Class 4 unitsComputational Thinking
Class 4
Chapter 11: Fun with Symmetry
A figure is symmetric if you can fold it along a line so the two halves match exactly. That fold-line is called a line of symmetry.
Learning outcomes
- Identify lines of symmetry in figures
- Complete symmetric drawings
Activities
- Mirror-fold paper symmetry
Worked examples
Read through these first, then try the practice below.
Example 1 — Lines in a square
How many lines of symmetry does a square have?
Solution: A square has 4 lines of symmetry: 2 through opposite sides and 2 through the diagonals.
Example 2 — Symmetric letter
Is the letter A symmetric?
Solution: Yes — A has one vertical line of symmetry through its top.
Self-do practice
Question 1 of 3 · Score 0/0How many lines of symmetry does an equilateral triangle have?
Sign in as a student in this class to save your progress.