100 PTS PLEASE HELP I DO NOT UNDERSTAND!!!!
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Answer:
Solution given;
m<DCA=<BCA[diagonal of a parallelogram or rhombus bisect the angle]
13x-16=9x+4
13x-9x=16+4
4x=20
x=20/4
x=5.
now
2<ADB+<BCD=180°[co interior angle]
2<ADB=180-13*5+16-9*5-4
<ADB=82/2
<ADB=41 ° is a required answer.