Cramer’s Rule Exam — 3×3 (interactive)

Paste a 3×4 augmented matrix as JSON (e.g. [[1,2,3,4],[4,5,6,7],[7,8,9,10]]). The last column are constants.

|A| — Cofactors by columns

|A1| — Replace column 1 by constants; expand by rows

|A2| — Sarrus

|A3| — Gaussian elimination (triangular)

Applied operations:

Final answers (student enters their computed determinants and solution)