Politicians make decisions difficult because they have to accept controversial proposals. Which is the result of all political elections.
Approach
+ - =
Wherw is the problem: plus, minus, just as a political-mathematical problem :) The mathematical formula + and - the result is = the basic idea in making political decisions.
Results
+ - =
Mathematicians plus, minus and equally shape their faces, and the eyebrows serve to make no mistake in their decision, because the decisions must be transparent !