Answer: positive
We're adding a negative to a positive. The sign of number that is larger in magnitude will determine the sign of the answer.
The 4.3 is negative while the 14.5 is positive. The 14.5 is larger than 4.3, so the sign of 14.5 will be the sign of the answer. This is why the final answer is positive.
You can think of (-4.3) + 14.5 as 14.5 + (-4.3) = 14.5 - 4.3 if it helps you see why the answer is positive.
