qcircle c1 0 0 50
qcircle c2 20 0 10
qcircle c3 0 20 10
circ2d3Tan tan1 c1 c2 c3

checklength tan1_1 -l 168.36566348025758
checklength tan1_2 -l 244.52937099154383
checklength tan1_3 -l 131.42863607625242
checklength tan1_4 -l 182.73062928272694
checklength tan1_5 -l 182.7306292827268
checklength tan1_6 -l 131.42863607625236
checklength tan1_7 -l 94.936311385359318
checklength tan1_8 -l 178.56704904481091