(a_11)(x_1) + (a_12)(x_2) = b_1
(a_21)(x_1) + (a_22)(x_2) = b_2
has a solution with x_1 and x_2 integers for all integers b_1 and b_2 if and only if D(A_1, A_2) = +/- 1. Interpret this result geometrically.
This solution is a proof regarding a matrix and the solution of a system of equations provided in an attached Word document.