9 - 12u + 4 + 6u > -5

Combine the 9 and the +4 as +13
Combine the -12u and the +6u as -6u

         13 - 6u >  -5

Subtract 13 from both sides:

         13 - 6u >  -5
        -13        -13 
       -----------------
             -6u > -18

Now we will divide both sides by -6,
remembering the rule:

1. If you divide both sides of an inequality by a 
   POSITIVE number, you DO NOT reverse the symbol
   of inequality.

2. If you divide both sides of an inequality by a 
   NEGATIVE, number you DO reverse the symbol
   of inequality.  
   
Here we want to divide both sides of

             -6u > -18

by the coefficient -6, and since -6 is NEGATIVE,
we DO reverse the symbol of inequality:

        -6u/(-6) < -18/(-6)

and upon simplifying we have

               u < 3

which we graph on a number line as 

<======================o-------
 -4 -3 -2 -1  0  1  2  3  4  5

or sometimes as

<======================)-------
 -4 -3 -2 -1  0  1  2  3  4  5

and sometimes write the solution set in
set-builder notation as 

{ u | u < 3 }  

or in interval notation as

(-¥, 3)

Edwin