Statics 6.73 - Determine the reactions at the supports at A, E and B of the compound beam. 

Hello, if we look at the figure the at B there is a link attached to it. So similarly to what we did for the link CD, we disconnect this link at B and replacing it with a force that is in the line of action of the link. In this case this link was totally vertical and that's why only By is included. I hope this clarifies your question!

Hi, the question did not ask for the forces at point C. :)

Hello Marcel, sadly I will be really busy this last part of Fall2021 semester. But you could guide yourself by one of my shear and bending diagrams videos: 1 - ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-elnwOEDfLIk.html&ab_channel=LearningbyTeaching 2 - ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-l_khO0MLGKQ.html&ab_channel=LearningbyTeaching 3 - ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KvpedXCsPh4.html&ab_channel=LearningbyTeaching 4 - ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-fgJgnMECQzc.html&ab_channel=LearningbyTeaching

@@LearningbyTeaching Perfect! Thanks for the help

no need. there is no horizontal forces

Hello, thanks for the comment. I will try to write bigger for following problems!