Texas Instruments TI-89 Manual Book page 14

Example — Three Equations, Three Unknowns
1. Press 3 „ and set Exact/Approx to
2. Start
3. Press
and three unknowns.
4. Enter the coefficients:
a =
1,1
a =
2,1
a =
3,1
5. Press ‡ to solve the problem. The busy indicator on the
status line displays while the solution is calculated.
The values for x
x = 72à481
1
= M547à481
x
2
x = 670à481
3
TI-89 / TI-92 Plus / Voyage™ 200 PLT Simultaneous Equation Solver App
Simultaneous Equation Solver and select
D ¸ ¸ for a problem with three equations
3 3
a =
9 8
1,2
= M
a
5 6
2,2
a =
1 5
3,2
, x
1
a = b1
7
1,3
= M
a b1
4
2,3
a = b1
9
3,3
, and x are displayed:
2 3
.
Exact
=
2
1
=
2
2
=
7
3
.
New
Page 14