Sharp EL9900C EL-9900C - Page 130

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 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) CONCEPT 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. 1. Enter the coefficients as elements in a matrix. 2. Use the rrowEF function to obtain the reduced row echelon form. 120