In this lesson, students investigate circle sectors. A sector is a region of a circle enclosed between 2 radii. Students look for and express regularity in repeated reasoning (MP8) as they make sector area and arc length calculations and use their findings to create a general method for finding sector areas and arc lengths.
Building intuition about arc length and fractions of circles will be helpful as students develop a definition of radian measure in an upcoming lesson.
- Generalize (orally and in writing) methods for calculating lengths of arcs and areas of sectors in circles.
- Let’s analyze portions of circles.
- I can calculate lengths of arcs and areas of sectors in circles.
The region inside a circle lying between two radii of the circle.