Question 256932
Using the Pythagorean theorem,
{{{A^2+B^2=C^2}}}
{{{5^2+10^2=C^2}}}
{{{C^2=25+100=125}}}
{{{C=5*sqrt(5)}}}
which violates your original statement "with integers for lenghths of sides" since this side is an irrational number and not an integer.