15a - 2a-a = 1,2

It looks like you have an algebraic expression or equation involving variables and perhaps some formatting issues. Could you please clarify or provide the full problem? For example, are you solving for \(a\) in the equation \(15a - 2a - a = 1.2\)? Or is there a different expression or question?

Once I have the complete and clear problem, I can assist you with the solution.