



 
Hi Jennifer, The augmented matrix for this linear system is \[ \left( \begin{array}{rrrr} To make the first entry in the second row equal to $0$ I would multiply the first row by 2 and add to the second row. The result is \[ \left( \begin{array}{rrrr} Wow! Multiply the second row by $\large \frac{1}{12}$ and the matrix becomes \[ \left( \begin{array}{rrrr} The second row is in the form you want for the third row so interchange the second and third row to get \[ \left( \begin{array}{rrrr} Can you see what to do now? Penny  


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