Simplify. consider all cases. |3x+12|

If anyone has done the algebra 2 chaos theory portfolio would you be wiling to me? i kind of know what i'm doing i just don't know if i'm doing it right.

Each of the walls of a room with square dimensions has been built with two pieces of sheetrock, a smaller one and a larger one. the length of all the smaller ones is the same and is stored in the variable small. similarly, the length of all the larger ones is the same and is stored in the variable large. write a single expression whose value is the total area of this room. do not use any method invocations.

Need solving this second acceleration problem.