Please help!!!! Matrices!!!
The following cryptogram was encoded with a 2x2 matrix:
8, 21, -15, -10, -13, -13, 5, 10, 5, 25, 5, 19, -1, 6, 20, 40, -18, -18, 1, 16
The last word of the message is _RON. What is the message? (_=0, A=1, B=2...)