This is not mathematics, this is symbol manipulation. The author is correct, the answer here is that it is a badly expressed problem - with multiple possible so

This is not mathematics, this is symbol manipulation. The author is correct, the answer here is that it is a badly expressed problem - with multiple possible solutions depending on the assumptions the audience makes. In mathematics allowing your audience to make assumptions is very very bad...people are terrible at making and applying assumptions - just look at any studies into eye witness testimony. Machines are just as bad, as they are loaded with assumptions of their programmers. As a Computer Scientist, I absolutely hate coming across badly expressed formulas. Abstraction is key - why are there parentheses around the 1+2, what makes those separate...why not just write 3?? - In fact there are no variables in this problem, it is constant, just give me the constant...or tell me why you have defined it this way. Implicit operations and ordering may save you a couple of characters but generate essays worth of confusion.