Answer:The fact ' is congruent to itself due to reflexive property' is not used to prove that
Step-by-step explanation:
Here we have a triangle PQR in which ST is the line segment which joins the points S and T where and
Now let
And, here PR is the common transversal which passes through the parallel lines ST and PQ.
So, In triangles PQR and STR,
( reflexive )
( by corresponding angle postulate)
Thus, ( by AA postulate of similarity)
Therefore, from the above proof we can say that except the fact ' is congruent to itself' we are using all the given options.