Step 1 :The elementary row operation used here is 'Row 2 = Row 2 - 2*Row 1'. This operation is used to make the leading coefficient of the second row zero.
Step 2 :The missing entry can be found by applying the same operation to the second column. That is, the missing entry is \(2 - 2*(1/3) = 2 - 2/3 = 4/3\).
Step 3 :So, the missing entry is \(4/3\).
Step 4 :The result of the operation is approximately 1.33, which is equivalent to \(4/3\) in fraction form.
Step 5 :Therefore, the missing entry in the matrix after the row operation is \(4/3\).
Step 6 :Final Answer: The missing entry is \(\boxed{\frac{4}{3}}\).