Answer
Multiplying the first row by $-4$ and then adding the result to the second row.
Work Step by Step
$$
\left|\begin{array}{rr}{2} & {-3} \\ {8} & {7}\end{array}\right|=\left|\begin{array}{cc}{2} & {-3} \\ {0} & {19}\end{array}\right|.
$$
Multiplying the first row by $-4$ and then adding the result to the second row.
