How to do plus and Minus sign in Mathcad Prime 4

Hi everyone, I've seen that this question has been asked before but not to Mathcad Prime 4.0. I've tried using the caracter map, insert the plus minus sign into a function but it does not recognize it as a function but a variable that you have to define. Some recommend to write some type of command so you can define the plus or minus character. Ok lets say that I obtain Plus and minus character from charactermap. What type of a function or equation should I define it on as to it gives me a asort of "multiplier" perhaps to any number I applied it on so it would give me the function of a plus or minus sign. I can not think of anything. I tried using matrices but I can not find such operator. Appreciate your advise. Thanks.