Draw Lines of Symmetry (Tutorial Only)

Learning Objectives Define 'line of symmetry' in their own words. Identify symmetrical and asymmetrical shapes. Use the 'fold test' to find a line of symmetry on a paper shape. Accurately draw lines of symmetry on simple 2D shapes like squares, rectangles, and hearts. Identify shapes that have one, more than one, or no lines of symmetry. Complete the other half of a symmetrical drawing when given one half and a line of symmetry. Have you ever noticed that a butterfly's wings are exactly the same on both sides? 🦋 That's called symmetry! In this lesson, we will learn about a special imaginary line called a 'line of symmetry'. You will learn how to find this line and draw it on different shapes. This helps us understand balance and patt...

TermDefinitionExample SymmetrySymmetry is when one half of an object is a perfect mirror image of the other half.A butterfly is symmetrical because its left wing is a mirror image of its right wing. Line of SymmetryThe line of symmetry is a line that divides a shape into two identical, matching halves. It's also called a 'mirror line'.The line drawn down the middle of a heart is a line of symmetry. Symmetrical ShapeA shape that has at least one line of symmetry.A square is a symmetrical shape because you can fold it in several ways to make the halves match. Asymmetrical ShapeA shape that has no lines of symmetry. No matter how you fold it, the two halves will not match up perfectly.A drawing of a hand is asymmetrical. Matching HalvesThe two equal parts of a shape that are c...

The Fold Test A line is a line of symmetry if folding the shape along that line makes the two halves match perfectly. Use this physical test with paper cutouts. If the edges of the folded shape line up exactly with no parts sticking out, your fold line is a line of symmetry. The Mirror Rule A line is a line of symmetry if it acts like a mirror, where one half of the shape is a reflection of the other half. Imagine placing a small mirror on the line. If what you see in the mirror plus the half-shape behind the mirror perfectly re-creates the original shape, it's a line of symmetry.