Question 388306
Use the cosine rule,
{{{b^2=a^2+c^2-2ac*cos(B)}}}
{{{cos(B)=(b^2-a^2-c^2)/(2ac)}}}
{{{cos(B)=(16^2-10^2-12^2)/(2(10)(12))}}}
{{{cos(B)=(12)/(2(10)(12))}}}
{{{cos(B)=1/20}}}
{{{highlight(B=87.1)}}}degrees