(0:01)Definition of Line of Symmetry: A line of symmetry divides a shape into two identical, mirror-image halves.

(0:24)Reflection Symmetry: Shapes like rectangles, squares, and circles have reflection symmetry because they have at least one line of symmetry.

(2:27)Mirror Points: Every point on one side of the line of symmetry has a corresponding mirror point on the other side, at equal distance from the line.

(3:01)Completing Shapes with Symmetry: Measure and mirror all vertices across the line of symmetry, then connect them.