Step 1: we know that angle t s r is-congruent-to angle q r s because all right angles are congruent. step 2: we know that angle t is-congruent-to angle q because it is given. step 3: we know that line segment s r is-congruent-to line segment r s because of the reflexive property. step 4: triangle t s r is-congruent-to triangle q r s because of the asa congruence theorem. of the aas congruence theorem. of the third angle theorem. all right triangles are congruent.