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Mathematics (2019) Grade(s): 4


Define a line of symmetry for a two-dimensional figure as a line across the figure such that the figure can be folded along the line into matching parts.

Unpacked Content


Students know:
  • Characteristics of lines of symmetry.


Students are able to:
  • Define a line of symmetry for a two-dimensional figure.
  • Identify and draw lines of symmetry for two-dimensional figures.


Students understand that:
  • a line of symmetry divides a shape into two parts such that when folded on the line, the two parts match.


  • Symmetry
  • Two dimensional figure
  • Line of symmetry