Rachel needs to wite 3 book reports with b pages and 3 science reports with s pages during the school year. Write an algebraic expression for the total number of pages Rachel will need to write.

F (x) = 3b+3s. This is the answer, because b and s is like your x. They're what you multiply by to get the number of pages. So if b and s equaled 3 you would plug 3 into b and s. So it'd be f (x) = 3 (3) + 3 (3) which equals your answer