Canonical form simplex method

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In 2-phases simplex method what kind of operations must be done to get the canonical form tableau?

In this step(phase 2 of 2-phases method) after the remotion of artificial variables columns of auxiliary problem and copy of coefficents of objective functions, I don't know what are the operations performed to get canonical form tableau (as you see in the picture)

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the objective function was

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To get the matrix back in canonical form, you simply need to make sure that any basic variable has a 0 coefficient in the objective function row. So looking at the matrix

$$\begin{bmatrix} 1&0&-1&-1&0&2 \\ 0&0&-4&-4&1&10 \\ 0&1&3&1&0&4 \\ -2&-1&2&0&0&0 \\ \end{bmatrix}$$

You simply need to add 2 times the first row to the last (objective row) and 1 times the third row to the last (objective row). This will make sure there is a coefficient of 0 in the objective row for the first two columns, since they are the columns that contain the basic variables.

Doing this, you should get that after adding $R4 + 2R1$ you get $$\begin{bmatrix} 1&0&-1&-1&0&2 \\ 0&0&-4&-4&1&10 \\ 0&1&3&1&0&4 \\ -2&-1&0&-2&0&4 \\ \end{bmatrix}$$ This makes sure that the basic variable $x_1$ has a 0 coefficient in the objective function row. Doing the same for the basic variable $x_2$, adding $R4+R3$, you should get:

$$\begin{bmatrix} 1&0&-1&-1&0&2 \\ 0&0&-4&-4&1&10 \\ 0&1&3&1&0&4 \\ -2&0&-3&-1&0&8 \\ \end{bmatrix}$$

Which is the matrix in canonical form.