arithmetic or geometric?

tn=2n+3
n=1:  2(1)+3=5
n=2:  2(2)+3=7
n=3:  2(3)+3=9
n=4:  2(4)+3=11
arithmetic

In this problem, you are trying to figure out if the equation is arithmetic or geometric.  For this problem you simply just plug in a number and simplify the problem.  For the "n" in the problem, you plug in the numbers one, two, three, and four.  So for the first one you plug number one into n and solve it and you get 5.  Next, you have n equals 2.  You plug in number two into the problem and you get 7.  Then, you have n equals 3.  You plug in number 3 into the problem and solve it and you get 9.  Finally the last number you plug into the problem is 4 and when you solve this you get 11.  Now your answer you have cummulated are 5,7,9, and 11.  So you look at your answer and you try to find the pattern they have.  Are the numbers added together or are they divided?  If they are added together that means the problem is arithmetic.  If they are divided by each other then that means the problem is geometric.  For this problem you add two for each answer so this must mean that the problem is arithmetic.