Question

17 what additional information is needed to prove that the triangles are congruent by hl? s t a r

Explanation:

Step1: Recall HL - Hypotenuse - Leg

The HL (Hypotenuse - Leg) congruence theorem for right - triangles states that if the hypotenuse and one leg of a right - triangle are congruent to the hypotenuse and one leg of another right - triangle, then the two right - triangles are congruent.

Step2: Analyze given information

We have right - triangles $\triangle SRT$ and $\triangle ART$. We know that $SR = AR$ (the marked congruent legs).

Step3: Determine missing information

To use HL, we need to know that the hypotenuses are congruent. So we need to know that $ST=AT$.

Answer:

We need to know that the hypotenuses $ST$ and $AT$ are congruent.