standard_description: Classify two-dimensional figures based on the presence or absence of parallel or perpendicular lines, or the presence or absence of angles of a specified size. Recognize right triangles as a category, and identify right triangles.
problem_activity: Task
Mr. Watkins asked his students to draw a line of symmetry for a circle
with center $O$ pictured below:
[IMG]
Lisa drew the picture below. Is Lisa correct?
[IMG]
Brad drew the picture below. Is Brad's picture correct?
[IMG]
How many lines of symmetry does a circle have? Explain.
Explain why  each line of symmetry divides the circle in half.
Explain why each line of symmetry for the circle must go through the center.


aligns: no