8^2+15^2=64+225=289=17^2
cosA=8/17
AD^2=DB^2+AB^2-2DB*AB*COSADB
r^2=r^2+289-2*r*17*8/17
16r=289
r=289/16
r=18,0625
8^2+15^2=64+225=289=17^2
cosA=8/17
AD^2=DB^2+AB^2-2DB*AB*COSADB
r^2=r^2+289-2*r*17*8/17
16r=289
r=289/16
r=18,0625