Since angles S and L are congruent, the triangle SLV is isosceles with base SL, that means SV = LV.
Since SV = m, we have LV = m
Now, to calculate the hypotenuse, we can use Pythagorean theorem:
[tex]\begin{gathered} SL^2=SV^2+LV^2 \\ SL^2=m^2+m^2 \\ SL^2=2m^2 \\ SL=m\cdot\sqrt[]{2} \end{gathered}[/tex]