Can you determine if a triangle is a right triangle by knowing its side lengths?

Yes, you can determine if a triangle is a right triangle by using the Pythagorean theorem. According to this theorem, if the lengths of the sides of a triangle are (a), (b), and (c) (where (c) is the longest side), the triangle is a right triangle if (a^2 + b^2 = c^2). If this condition holds true, the triangle has a right angle.