Lesson: Circles Mathematics • 11th Grade

Students will be able to

• recall the definition of a circle and the different parts of a circle,
• understand that all circles are similar,
• understand the condition required for the congruence of two circles (same radius/diameter),
• understand that any line passing through the center of a circle is a line of reflectional symmetry,
• understand basic relationships between the parts of a circle, such as
  • the diameter is twice the radius,
  • the diameter passes through the center of a circle,
  • a chord divides a circle into a major and minor segment,
• understand that any two radii of a circle and the chord that connects them form an isosceles triangle,
• understand that if chords of the same length connect radii in the same circle (or in congruent circles), then the two isosceles triangles formed are congruent,
• use the basic relationships between the parts of a circle and triangles to find unknown angles or lengths.