To solve for x in an inequality is very similar to solving for x in an equation since for both you would need to isolate x.
step 1) -2x-4>8 add the 4 over to move any constants over to the +4 +4 other side.
-2x> 12
step 2) x< -6 Divide out the -2 to isolate x, however, keep in mind, when you divide or multiply over any negative number, you must also remember to flip the inquality sign.
Answer: x<-6