Question 125885

{{{Vertical}}} angles have the {{{same}}} degree measurement.
 
Two angles are {{{complementary}}} if their measures add up to {{{90}}}.

so, you will have:

angle {{{A}}}
angle {{{B}}}

by the definition above {{{A=B}}}

and {{{2A=90}}}

{{{A=90/2}}}

{{{A = 45^o}}}.........=> and angle {{{B=45^o}}}