melody , i think anonymous is right because as there is 5x so 2x can also be the same ! but anonymous i think ur way wasnt a bit correct !
(5x+4)+(2x1)
so i assume this will be done like this ,
5x-4+2x
=5x+2x-4
=7x-4
so thats the answer but if that 2"x" is really multiplication sign or a variable , then pls let me know !