What is Symmetry?
How can you tell if a shape is symmetrical?
Goal:
Goal:
Some shapes, like a square or rectangle, have multiple lines of symmetry, while others, like some trapezoids, have none. View the video that follows to learn more about identifying lines of symmetry in shapes.
Symmetry
A line of symmetry is a line that splits a shape into two exact equal parts. A shape is symmetric if it has one or more lines of symmetry.
Heart
A heart has one line of symmetry – right down the middle. The heart is the same on each side of this line. This is not a line of symmetry because the heart is not equal on each side of the line.
Star
A star has more than one line of symmetry – 1, 2, 3, 4, 5. This star has 5 lines of symmetry.
Triangle
A triangle has 3 lines of symmetry. Each goes through one of the corners and across to the other side.
Rectangle
Lastly, a rectangle has 2 lines of symmetry—1, 2.
What does it mean for a shape to be considered symmetrical?