as we know to draw the system curve of a piping system we have to change the value of Q total and get a head for each value we put in the following equation : H=Hstatic +Kq^2 where K is the sum of major and minor losses. what if we have a piping system that have many branches "tree -system" , how can we plot the system curve then ? if we take the longest run and apply the above equation the change in Q all along the pipe will interrupt our calculation because the foumula will look like the following: H=hst +K1Q1+K2Q2+K3Q3 .... BUT usuallly for a single pipe system we have 1 Q all along the pipe which is the total Q , what do we do in the case of branched system ?