Count Lines of Symmetry

Learning Objectives Define 'line of symmetry' in their own words. Identify if a shape is symmetrical or asymmetrical. Find and draw all lines of symmetry on a given 2D shape. Count the total number of lines of symmetry for common shapes like squares, rectangles, and triangles. Explain why a line is or is not a line of symmetry using the 'fold test'. Complete the other half of a symmetrical shape when given one half and a line of symmetry. Have you ever folded a piece of paper in half to make a heart? ❤️ That fold line is a line of symmetry! Today, we are going to become symmetry detectives! We will learn what a line of symmetry is, how to find these special lines in different shapes, and how to count them. This helps us understand patterns and shapes all...

TermDefinitionExample SymmetrySymmetry is when one half of a shape is a mirror image of the other half.A butterfly is symmetrical because its left wing looks exactly like its right wing. Line of SymmetryThe imaginary line where you could fold a shape in half so that both sides match up perfectly.The line down the middle of the letter 'A' is a line of symmetry. Symmetrical ShapeA shape that has at least one line of symmetry.A square is a symmetrical shape. Asymmetrical ShapeA shape that has zero lines of symmetry. No matter how you fold it, the two halves will not match.The letter 'J' is an asymmetrical shape. Vertical Line of SymmetryA line of symmetry that goes straight up and down.The line that splits the letter 'M' into two matching parts. Horizontal Line...

The Fold Test A line is a line of symmetry if, when the shape is folded along that line, the two halves match exactly. Use this test to check if any line you draw is a true line of symmetry. Imagine folding the shape along your line. Do the edges and corners line up perfectly? Regular Polygon Rule Number of Sides = Number of Lines of Symmetry For regular polygons (shapes where all sides and all angles are equal), the number of lines of symmetry is the same as the number of sides. For example, a square has 4 equal sides, so it has 4 lines of symmetry.