Answer:
[tex]m=18.7\ in[/tex]
Step-by-step explanation:
see the attached figure to better understand the problem
Applying the law of cosines
[tex]m^2=j^2+k^2-2(j)(k)cos(M)[/tex]
substitute the given values
[tex]m^2=21^2+12^2-2(21)(12)cos(62^o)[/tex]
[tex]m^2=348.39\\m=18.7\ in[/tex]
