HP 48gII User Manual page 355

To start the process of forward elimination, we divide the first equation (E1) by
2, and store it in E1, and show the three equations again to produce:
Next, we replace the second equation E2 by (equation 2 – 3×equation 1, i.e.,
E1-3×E2), and the third by (equation 3 – 4×equation 1), to get
Next, divide the second equation by –8, to get
Next, replace the third equation, E3, with (equation 3 + 6×equation 2, i.e.,
E2+6×E3), to get
Notice that when we perform a linear combination of equations the calculator
modifies the result to an expression on the left-hand side of the equal sign, i.e.,
an expression = 0. Thus, the last set of equations is interpreted to be the
following equivalent set of equations:
X +2Y+3Z = 7,
Page 11-29