Respuesta :

    -4 = 8m + 18n
-18n = 8m + 4
 /-18    /-18  /-18
     n = 8m/-18 + 4/-18
     
I'm not sure so yeah
-4 = 8m + 18n (Original problem)
-8m -8m. (Subtract 8m from both sides)
-4 -8m = 18n (Divide both sides by 18)
-4 -8m/18 =n (Answer)