14429
By adding numbers, I refer to introducing new digits that aren't presented in the first number we are given
For example:
If I said "1 + 4 + 4 + 2 - 2 = 9" That would be incorrect, because the number we are using is 14429 not 144229.
You also can't ignore numbers or use numbers in a different order. HOWEVER, you can use BODMAS.
1^4 + 4 x 2 = 9
(There I used BODMAS to change the order of operations, however, I didn't change the physical order of the numbers

)