Geometry January 4, 2011

1. Geometry January 4, 2011 Get out: pencil, binder, homework and begin do now silently. Objectives: SWBAT • Use circle vocabulary in context to describe drawings and relationships • Determine relationships between tangents and between radii and tangents • Agenda: • Do Now (10 min) • Tangent Investigation (15 min) • Investigation Debrief (10 min) • Practice Problems (15 min) • HW: tangent worksheet

2. Do Now Circle Drawing P K R A T Objectives: SWBAT Use circle vocabulary in context to describe drawings and relationships Determine relationships between tangents and between radii and tangents

3. Investigation Debrief • Investigation 1: If a radius is drawn to a point of tangency on a circle, then • the two segments are perpendicular --OR-- • the angles formed are right angles Objectives: SWBAT Use circle vocabulary in context to describe drawings and relationships Determine relationships between tangents and between radii and tangents Obj: Students will use circle vocabulary accurately to describe elements and relationships between elements in a circle. Students will determine the relationships between tangents and radii in a circle.

4. Investigation 2 debrief • If two tangents are drawn from the same point outside a circle, then the tangent segments are congruent Objectives: SWBAT Use circle vocabulary in context to describe drawings and relationships Determine relationships between tangents and between radii and tangents

5. Practice Time • Work on problems 1 – 5 with a partner. When you are done, raise your hand to receive your homework. Objectives: SWBAT Use circle vocabulary in context to describe drawings and relationships Determine relationships between tangents and between radii and tangents