-129 is the anwser to ur problem
9x^2 and 5x are not like terms because 9x is being squared and 5x isn't.
Aritmetic increases by the same number
geometric has 1 number that each term is multiplied by to get the next term
4 to 9 is 5
9 to 13 is 4
not same difference
9/4=13/9?
81/36=52/36?
no
neither aritmetic nor geometric
