HP 50g User Manual page 357

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.,
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