1.if tip included in fare, total amount paid by Angela =(55$/x) +8$
if tip is not included in fare than total amount paid by angela = (63$/x)+8$
Explanation :-
According to qus
Total friends included Angela = x
Total fare paid by them =63$
If tip included in total fare, than total fare without tip=63-8
= 55$
Sothat,
amont paid by individual =total fare /total friends. 55$/x
If tip not include in total fare than total amount paid by individual =63$/x