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Reflectional symmetry (also called lines of symmetry) occur when a line splits a shape into 2 mirror images. Some people like to think about this as folding a shape in half.
Now we are going to explore how many lines of symmetry a shape has. Since a line of symmetry splits a shape in half, it hopefully makes sense that the line needs to go through the center of the shape. Also, a line would need to pass through the midpoint (or middle) of each side. Finally, a line needs to divide each angle in half.
Use your segment tool to draw in segments that meet the following conditions:
1. The segment splits the shape into 2 mirror images.
2. Each segment MUST go through the center of the shape (in this case, G).
3. Each segment MUST go through either a midpoint, a vertex (angle) or both.
4. Each midpoint and vertex must have one segment through it.
11. How many lines of symmetry does the equilateral triangle have?