the answer in attached figure
we know that
sin(30°)=0.5 cos(30°)=√3/2
sin(60°)=√3/2 cos(60°)=0.5
sin(60)=BC/AC=5√3/10=√3/2-------------- is ok
cos (60)=AB/AC=5/10=0.5---- is ok
sin(30)=BA/AC=5/10=0.5-------------- is ok
cos (30)=BC/AC=5√3/10=√3/2-------------- is ok
if angle B is 90°
then
AB²+BC²=AC²------------> 5²+(5√3)²=10²=(25+75)=100------------- > is ok
the solution in the attached figure
