Multiply them across. Like this
14-8=-112
1419i=266i
-5i-8=40i
-5i19i=-95i^2
-112+266i+40i-95i^2
First before combining like terms, you first turn -95i^2 to 95 because i^2 is -1. Then you multiply -1, which was i^2, with -95, which will give you 95.
So now you -112+266i+40i+95
Combine like terms which will be: -112+95= -17
266i+40i= 306i
So now your answer will be -17+306i