Answer
$m\angle A=30$
$m\angle B=60$
Work Step by Step
It is given that $m\angle A=\frac{1}{2}m\angle B$.
$m\angle A+m\angle B=90\longrightarrow$ definition of complementary
$\frac{1}{2}m\angle B+m\angle B=90\longrightarrow$ substitution
$1.5m\angle B=90\longrightarrow$ combine like terms
$m\angle B=60\longrightarrow$ division property of equality
Substitute to find $m\angle A$.
$m\angle A=2m\angle B=\frac{1}{2}(60)=30$
