Find the exact value of the following expression without using a calculator. Note: Enter an exact simplified answer with no decimals. Use pi for r if necessary.
Enter none if there is no answer.

in if you ask questions, the points are taken from your total and given to the one who answered it..

so if i have 30 points and i ask a question for 5 points, then when someone asks a question i will lose 5 points and the answerer earns 5

happy to

you have to find the same variables -3n - 5n so this would be -3n +(-5n) which equals -9n