Lets suppose we have a right triangle:
where the longest side is opposite of the right angle. (10 in our case).
Since we have a right triangle, Pythagorean theorem must be fulfilled:
[tex]6^2+8^2=10^2[/tex]
Which gives
[tex]\begin{gathered} 36+64=100 \\ 100=100 \end{gathered}[/tex]
Since the left and right sides are equal, the given triangle is a right triangle.
