Question 109523
From the Pythagorean theorem, you know that for right triangles,
{{{S[1]^2+S[2]^2=H^2}}}
where {{{S[1]}}} and {{{S[2]}}} are the sides and {{{H}}} is the hypotenuse. 
{{{5^2+10^2=H^2}}}
{{{H^2=125}}}
{{{H=11.18}}}