Answer:
[tex]m\angle ABC=90^o[/tex]
Step-by-step explanation:
see the attached figure to better understand the problem
we know that
[tex]m\angle ABC=m\angle ABD+m\angle DBC[/tex] ----> by angle addition postulate
substitute the given values
[tex]m\angle ABC=35^o+55^o=90^o[/tex]
