1 3 - и - 6 8

I’m not totally sure what the layout represents. Could you confirm what you want to do with those numbers? Here are two common interpretations and solutions:

• If it’s a 2×2 determinant with the matrix [ [1, 3], [6, 8] ] then the determinant is: det = 1·8 − 3·6 = 8 − 18 = −10.

• If you meant something else (a 3×3 matrix, or a system of equations, or the middle entry “i” being the imaginary unit), please provide the full matrix or describe the task (e.g., “solve the system,” “compute the determinant,” etc.). If you can paste the exact problem statement or reformat the grid, I’ll solve it step by step.