Evidence of Understanding

**describe qualities of polygons**- use
**examples**and**non-examples**to justify a figure is a**polygon** - distinguish
**irregular**and**regular**polygons using congruent sides and congruent angles - create and justify all of the lines of symmetry for a regular polygon (use paper folding, drawing, reflective devices, etc.)
- use isosceles triangles to understand qualities about regular polygons
- decompose regular polygons into congruent triangles
- use properties of circles to construct an
**equilateral**triangle - use properties of circles to construct a regular hexagon
**inscribed**in a circle

- use
**explore congruent parts of regular polygons using lines of reflection and center of rotation**- demonstrate how
**rotational symmetry**and**line symmetry**carry a polygon onto itself- describe rotations as preserving congruence (
**isometry**) and**orientation**

- describe rotations as preserving congruence (
- use tools to justify that the
**line of symmetry**, or**line of reflection**, is the**perpendicular bisector**- construct the perpendicular bisector
- explain that the distance of each point of the figure from the line of reflection (line of symmetry) is the same

- generalize qualities about regular polygons using rotational and line symmetry
*Example: connect lines of symmetry with congruent parts within a polygon and the degree of rotation that carries a polygon onto itself*

- specify the reflection or rotation that carries a polygon onto itself
- calculate the degree measures that can carry a polygon onto itself
- use the coordinate plane to write the equation of a horizontal or vertical line that carries a polygon onto itself

- demonstrate how

Develop conceptual understanding:

polygon, regular polygon, irregular polygon, equilateral, inscribed, rotate, reflect, rotational symmetry, line symmetry, isometry, orientation, line of symmetry, line of reflection, perpendicular bisector

Supporting terms to communicate:

examples, non-examples, congruent, side, angle, triangle, square, pentagon, octagon, preserve, perpendicular, bisect, degree measure, clockwise, counterclockwise