Perform one step of row reduction, in order to calculate the values for and by back substitution.
Then calculate the values for and for . Also calculate the determinant of the original matrix.

You can let webwork do much of the calculation for you if you want (e.g. enter 45-(56/76)(-3) instead
of evaluating it and then entering it). You can also use the preview feature in order to make sure
that you have used the correct syntax in entering the answer.

(Note: since the determinant is unchanged by row reduction it will be easier to calculate the
determinant of the row reduced matrix.)