How would you solve 2 to the a plus 3 equals 3 to the 2a minus 1?

Please resubmit your question spelling out the symbols as "plus", "minus", "times", "divided by", "equals", "squared", "cubed" etc. Please use "brackets" (or parentheses) because it is impossible to work out whether "x plus y squared" means x + y^2 or (x + y)^2. You will need to use a code, for example b1 (open bracket) and b2 (close bracket), because the browser will reject brackets!
Here, it is not clear whether you mean 2^a + 3 or 2^(a+3)