What is the answer for 9r2s plus 4rs plus 5s2-9s2-9r2-5rs-s2 plus 2r2s plus 4rs plus 2s2?
There is no answer as expressed, since it is not a question.
Are you trying to simplify it?
9r2s + 4rs + 5s2 - 9s2 - 9r2 - 5rs - s2 + 2r2s + 4rs + 2s2
= (9 + 2)r2s + (4 - 5 + 4)rs + (5 - 9 - 1 + 2)s2
= 11r2s + 3rs -3s2
= s(11r2 + 3r -3s)