Step-by-step explanation:
A triangle has three angles that add up to 180°.
If we know two opposite angles are equal, like the triangle above, then we know that the third angle is equal as well.
Also, if opposite angles are equal, then we can assume that opposite sides are equal too.
1. So, since line RS is an angle bisector of triangle PRQ, angle P = angle Q by the reflexive property.
2. Since angle P = angle Q, triangle PRS and triangle QRS are congruent.
3. Because those two triangles are congruent, their hypotenuse, or longest sides, are congruent as well.
Hope this helps!