A scalene triangle can never be an isosceles triangle. How? Well, let's take a look at the definition of a scalene triangle. In short, a scalene triangle is a classification of a triangle that does not have any congruent sides. On the other hand, an isosceles triangle is a triangle in which its legs are both congruent. Therefore, if a scalene triangle has two congruent legs, it wouldn't even be a scalene triangle, but instead it would be an isosceles triangle. Hope this helped!