S=1/2(u+v)t
i. u as subject
ii. V as subject

Answer:
i. [tex]u=\frac{2s}{t}-v[/tex]
ii. [tex]v=\frac{2s}{t}-u[/tex]
Explanation:
i.)
[tex]s=\frac{1}{2}(u+v)t\\\\2s=(u+v)t\\\\\frac{2s}{t}=u+v\\\\\frac{2s}{t}-v=u[/tex]
ii.)
[tex]s=\frac{1}{2}(u+v)t\\\\2s=(u+v)t\\\\\frac{2s}{t}=u+v\\\\\frac{2s}{t}-u=v[/tex]