equations of the system Ax-4y=9, 4x+By=-1 explain how to find the values of A and B,then find these values
from the 1st:
A = (9+4y)/x
from the 2nd:
B = (-4x-1)/y
without more information or explicit values of x and y, that is it.
A = (9+4y)/x
from the 2nd:
B = (-4x-1)/y
without more information or explicit values of x and y, that is it.