ALEX Classroom Resources

   View Standards     Standard(s): [MA2015] GEO (9-12) 24 :

24 ) Prove that all circles are similar. [G-C1]

[MA2019] GEO-19 (9-12) 20 :

20. Derive and apply the formula for the length of an arc and the formula for the area of a sector.

[MA2019] GEO-19 (9-12) 37 :

37. Investigate and apply relationships among inscribed angles, radii, and chords, including but not limited to: the relationship between central, inscribed, and circumscribed angles; inscribed angles on a diameter are right angles; the radius of a circle is perpendicular to the tangent where the radius intersects the circle.

Module 5, Topic B defines the measure of an arc and establishes results relating to chord lengths and the measures of the arcs they subtend. Students build on their knowledge of circles from Module 2 and prove that all circles are similar. Students develop a formula for arc length in addition to a formula for the area of a sector and practice their skills solving unknown area problems.