4-1-2

Simultaneous Linear Equations

Example

To solve the following simultaneous linear equations for x, y, and z

 

4x + y

– 2z

= – 1

 

x + 6y

+

3z

= 1

 

– 5x + 4y +

z

= – 7

Procedure

1m EQUA

21(SIML)

2(3)

3ewbw-cw-bw bwgwdwbw -fwewbw-hw

41(SOLV)

Result Screen

#Internal calculations are performed using a 15- digit mantissa, but results are displayed using a 10-digit mantissa and a 2-digit exponent.

#Simultaneous linear equations are solved by inverting the matrix containing the coefficients of the equations. For example, the following shows the solution (x1, x2, x3) of a simultane- ous linear equation with three unknowns.

 

 

 

 

 

 

 

 

–1

 

 

x1

=

 

a1

b1

c1

 

 

d1

x2

 

a2

b2

c2

 

 

d2

x3

 

 

 

a3

b3

c3

 

 

 

d3

Because of this, precision is reduced as the value of the determinant approaches zero. Also, simultaneous equations with three or more unknowns may take a very long time to solve.

#An error occurs if the calculator is unable to find a solution.

#After calculation is complete, you can press

1 (REPT), change coefficient values, and then re-calculate.

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