Recall that in a scalene triangle all the sides
have different lengths and all the interior angles have different measures. In
such a triangle, the shortest side is always opposite the smallest angle. Similarly,
the longest side is opposite the largest angle.
In the figure above, drag any vertex of the triangle
and see that whichever side is the shortest, the opposite angle is also the
smallest. Then click on 'show largest' and see that however you reshape the
triangle, the longest side is always opposite the largest interior angle.