Sharp EL-9900 - Manual (Page 130)

120
Chapter 8
Matrix Features
Within the Matrix features, up to ten different matrices can be entered.
To get to the Matrix features, press @ m. Define and edit the matrices within
this mode too.
1. Try it!
Three equations can be derived as follows, containing three
unknown quantities:
3x + 2y + z = 39
2x + 3y + z = 34
x + 2y + 3z = 26
x , y and z represent the price for each sheaf of the first, second
and third class crops, respectively.
You can solve the above system of linear equations by using a
matrix.
CONCEPT
1. Enter the coefficients as elements in a matrix.
2. Use the rrowEF function to obtain the reduced row echelon
form.
Three sheaves of the first class crop, two of the
second, and one of the third are sold for 39
dollars. Two of the first, three of the second and,
one of the third for 34 dollars. And one of the
first, two of the second and three of the third for
26 dollars. How much did you receive from each
sheaf of the first, second and third class crops?
(Chapter VIII of Chiu Chang Suan Shu - Nine
Chapters of Arithmetic Arts, 200 B.C., China)