To solve the first equation, we need to isolate the variable "x":
3114 - 279 = 5x
2835 = 5x
Divide both sides by 5:
x = 567

Now, let's solve the second equation for variable "a":
48709 - 469a = 597
Subtract 48709 from both sides:
-469a = -48112
Divide both sides by -469:
a = 102

Finally, let's solve the third equation for variable "a":
37183 - 89a = 3987
Subtract 37183 from both sides:
-89a = -33196
Divide both sides by -89:
a = 372