Texas Instruments TI-84 - Manual (Page 509)

Chapter 17: Activities 506
Computing Areas of Regular N-Sided Polygons Computing Areas of Regular N-Sided Polygons Computing Areas of Regular N-Sided Polygons Computing Areas of Regular N-Sided Polygons
Problem Problem Problem Problem
Use the equation solver to store a formula for the area of a regular N-sided polygon, and
then solve for each variable, given the other variables. Explore the fact that the limiting
case is the area of a circle, pr
2
.
Consider the formula A = NB
2
sin( pàN) cos(pàN) for the area of a regular polygon with N
sides of equal length and B distance from the center to a vertex.
Procedure Procedure Procedure Procedure
1. Press

0 to select 0:Solver from the MATH menu. Either the equation editor or
the interactive solver editor is displayed. If the interactive solver editor is displayed,
press
} to display the equation editor.
2. Enter the formula as 0=A N NB
2
sin( p / N)cos( p / N) , and then press
Í. The
interactive solver editor is displayed.
N = 4 sides N = 8 sides N = 12 sides