You can put this solution on YOUR website! Gather like terms and add/subtract them.
(4x^3-2x^2+x+4)+(9-x^5-x^2+4x)
Like if I was to say
(4 oranges-2 bananas+1 apple+4 lemons)+(9 lemons-1 grape-1 banana+4 apples)=
Then arrange the list so that the highest order of x is first , on down the line, and the constant is last in line.