Microsoft Excel is WRONG!!! Beware...
Ahhh, but you still have an error, Mr. devitg.
As I stated in my earlier post, negation is just multiplying by -1. To break down your example:
-5*-5 can be written as
-1*5*-1*5 and does indeed equal 25.
-1*5^2 does not. The 5^2 takes precedence according to the order of operations, then you multiply by -1 which gives the correct answer: -25
Again, I ask you to check this on any mathematics program, in any algebra book or by talking to a good math teacher. As I said before, if you are a premium member of this web site, you can use Mathematica to evaluate this one. If you type in only -5^2, you get -25.
Do you think a program written for mathematicians by mathematicians under a company run by Dr. Wolfram, the guy who had his PhD in theortical physics at age 20, would do it wrong, while the program from a dropout from Harvard would do it right? Yes I know Bill can add - he's got billions - but his subtraction needs some work...