Chapter 4 Equation Calculations; Simultaneous Linear Equations - Casio fx-9750GII User Manual

Equation Calculations
Chapter 4
From the Main Menu, enter the EQUA mode.
• {SIML} ... {linear equation with 2 to 6 unknowns}
• {POLY} ... {degree 2 to 6 equation}
• {SOLV} ... {solve calculation}

1. Simultaneous Linear Equations

You can solve simultaneous linear equations with two to six unknowns.
• Simultaneous Linear Equation with Two Unknowns:
a x b y
+ =
1 1
a x b y
+ =
2 2
• Simultaneous Linear Equation with Three Unknowns:
a x b y
+ +
1 1
a x b y
+ +
2 2
a x b y
+ +
3 3
1. From the Main Menu, enter the EQUA mode.
2. Select the SIML (Simultaneous) mode, and specify the number of unknowns (variables).
You can specify from 2 to 6 unknowns.
3. Sequentially input the coefficients.
• The cell that is currently selected for input is highlighted. Each time you input a coefficient,
the highlighting shifts in the sequence:
a b c
1 1
• You can also input fractions and values assigned to variables as coefficients.
• You can cancel the value you are inputting for the current coefficient by pressing
any time before you press
to what it was before you input anything. You can then input another value if you want.
• To change the value of a coefficient that you already stored by pressing
cursor to the coefficient you want to edit. Next, input the value you want to change to.
• Pressing (CLR) clears all coefficients to zero.
4. Solve the equations.
Example To solve the following simultaneous linear equations for
– 5
c
1
c
2
c z d
=
1 1
c z d
=
2 2
c z d
=
3 3
a b c
...
n n n
1
to store the coefficient value. This returns to the coefficient
x y z
4 + – 2 = – 1
x y z
+ 6 + 3 = 1
x y z
+ 4 + = – 7
n
( = 2 to 6)
4-1
4
at
, move the
x y z
, , and