Answer:
Step-by-step explanation:
AB=AD so <ABD=<ADB=72
<BDC=180-<ABD=180-72=108 ( cause A,D,C are on the same line)
<BAC=180-(<ABD+<ADB)=180- (72+72)=180-144=36
so <BCA=<BAC=36 cause AB=BC ( trg BAC is isosceles)
<BCD=<BCA=36 ( cause A,D,C are on the same line)
<CBD=180-(<BDC+<BCD)=180- (108+36)=180-144=36
so <CBD=<BCD=36 so the trg BCD is isosceles
