Question

plz show the process of solving it

Answer 1

v=30
now
1/rp=1/10+1/10
rp=5
re=10+5=15
i=v/r=30/15=2
V1=V2
i1r1=i2r2
10i1=10i2
i1=i2
but i=i1+i2
2=2i1
i1=1
so V1=i1r1=1×10
V1=10volt