Read the result
Only the target row changes for a replacement or scaling operation. A swap changes row order but not the equations represented by the system.
Matrix methods
Try a single row operation and see exactly which entries change.
Formula
R_i <-> R_j, R_i <- kR_i, or R_i <- R_i + kR_j
Row operations are the mechanics behind Gaussian elimination. The notation matters because it tells you which row changes.
Read the result
Only the target row changes for a replacement or scaling operation. A swap changes row order but not the equations represented by the system.
Where it helps
Use this to rehearse the row notation used inside Gaussian and Gauss-Jordan elimination.
Common slip
Scaling a row by 0 destroys information, so it is not an equivalent row operation.
Try it
Use R2 <- R2 + 1.5R1 on the default matrix and compare the new row with the Gaussian elimination step.