CK12 - Geometry

Comments:As in example1, the purposeof this exampleis to showthat the new area formulasdowork.
We can confirmthat the area formulagivesa correctanswerbecausewe haveanotherway to confirmthat
the area is correct.

LessonSummary

The lessoncan be summarizedwith a reviewof the formulaswe derived.

Perimeter Area

Any regularpolygon

Any regularpolygon

Regularpolygoninscribedin a unit circle

Pointsto Consider

We usedthe conceptof a limit in an earlierlesson.In the LessonExercises,you will havean opportunityto
use the formulasfrom this lessonto “confirm”the circumferenceand area formulasfor a circle,whichis the
“ultimate”regularpolygon(withmany, manysidesthat are very short).

LessonExercises

Eachside of a regularhexagonis incheslong.

1. Whatis the radiusof the hexagon?


2. Whatis the perimeterof the hexagon?


3. Whatis the area of the hexagon?

A regular -gon and a regular -gon are inscribedin a circlewith a radiusof centimeters.

4. Whichpolygonhas the greaterperimeter?


5. How muchgreateris the perimeter?


6. Whichpolygonhas the greaterarea?


7. How muchgreateris the area?


8. A regular -gon is inscribedin a unit circle.The area of the -gon,roundedto the nearesthundredth,

is. Whatis the smallestpossiblevalueof?

Answers

1. inches


2. inches