I have been working on homework and cant seem to grasp the right order or equation movements in.

AN example of a question would be

SOlve for both FB and FA using substitution

Given:

-FA cos(35) + FB cos(75)=0

-FA sin(35) +FB sin(75)= 235.4

Any help would be appreciated

THis is my work

-FA cos(35) +FBcos(75)=0

FB=FAcos(35)/cos(75)

substitute

-FAsin(35)+(FAcos(35)/cos(75))sin(75)=235.4

and then whatever i try seems to make no sense after that. I may be missing a rule or something but if any have explanations that would be awesome.