Proof for parallelogram
given PQRS is a parallelogram prove PR and QS bisect each other at T
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PR is not bisected if the two parts are 1 and 3
by definiton of paralleogram, PQ=SR, and PQ II SR
by alternate interior angles, <1=<3 and <2=<4 by ASA, triangles STR=QTP. then u should be able to fill up the rest using CPCTC and definition of bisector
We need to prove triangle PTQ is congruent to triangle STR. By parallelogram definition, lines PQ = SR Since PQ is parallel to SR then Angle QPT = angle TRS and angle PQT = angle TSR using ASA triangle PTQ is congruent to triangle STR and therefore line TS = TQ and line PT = line PR
so if we put this into a 2 column proof it would be
PQRS is a parallelogram reason= PQ=SR PQ is parallel to SR reason=Angle QPT = angle TRS and angle PQT = angle TSR Angle are congruent reason=ASA triangle PTQ is congruent to triangle STR line TS = TQ and line PT = line PR
No. 1. PQRS is paralleogram R- given 2. PQ=SR and PQ II SR R- def of paralleogram 3.<1=<3 and <2=<4 R- alternate interior angle theorem 4. Triangle STR=QTP R-ASA 5. ST=TQ and TP=TR R-CPCTC 6. SQ bisects PR R-definition of bisector
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