Computing And Graphing Mortgage Payments - Texas Instruments TI-84 PLUS - Graphing Calculator Manual Book

9. Press p. Set the viewing window.
Xmin=0
Xmax=200
Xscl=10
10. Press o. Turn off all functions and stat plots. Enter the equation for the area. Use
of . Set the graph styles as shown.
N
11. Press r. After the graph is plotted, press
Í. Notice that as
Press
188
approximately 113.097.
area of an N-sided regular polygon, with r as the distance from the center to a vertex,
approaches the area of a circle with radius r (pr

Computing and Graphing Mortgage Payments

Problem
You are a loan officer at a mortgage company, and you recently closed on a 30-year home
mortgage at 8 percent interest with monthly payments of 800. The new home owners want to know
how much will be applied to the interest and how much will be applied to the principal when they
make the 240th payment 20 years from now.
Procedure
1. Press z and set the fixed-decimal mode to
to the defaults.
Ymin=0 Xres=1
Ymax=150
Yscl=10
increases, the value of
X
2
(the area of the circle) is a horizontal asymptote to
Y2= p B
Í to trace to
100 X=100
converges to p6
Y
2
) as N gets large.
decimal places. Set the other mode settings
2
Chapter 17: Activities
in place
X
Í.
. Press
150
2
, which is
. The
Y1
323