i started Linear Algebra today and my teacher has a thick accent. To make it worse he doesn't explain what these new notations mean.

i cant find the latex code for systems so if anyone knows it please lemme in

$\displaystyle Equation 1: a_ii * x_i + ... + a_in *x_n = b_i$

$\displaystyle Equation 2: a_mi * x_i + ... + a_mn *x_n = b_m$

i understand generally what the equation is showing but the subscripts are terribly confusing to me.

second off Im pretty sure some of those i's are 1's but i couldnt tell the difference on the chalk board.