25 - 17(9 + 8) i keep getting different answers..

We must use the order of operations as expressed by the saying:

Please Excuse My Dear Aunt Sally

P = Parentheses
E = Exponent
M = Multiplication
D = Division
A = Addition
S = Subtraction

So, we start with the parentheses:

-25 -17(17)

Next, we complete the multiplication problem:

-25 -289

Now, we do the subtraction problem:

-314

Hope this helps!