We also want next to eliminate the \(-12\) in row \(3 .\) To do this, we must multiply 7 by \(12 / 7\) and add it to row 3 (recall that placing the value you wish to cancel out in the denominator of a...We also want next to eliminate the \(-12\) in row \(3 .\) To do this, we must multiply 7 by \(12 / 7\) and add it to row 3 (recall that placing the value you wish to cancel out in the denominator of a multiple and the value you wish to achieve in the numerator of the multiple, you obtain the new value).