....it really isn't that difficult. For instance:
3n2 + 5n +1 = 43
(bear with me, since I can't put that "2" as a "squared symbol")
...really means "3 times n times n [again] plus 5 times n plus 1, which will equal 43" . The "3" and the "5" are called coefficients, which are numbers in front of any variable (in this case, the n - that n is a variable, or an unknown quantity...well, for the time-being anyway)