qcircle c1 0 0 10
qcircle c2 30 0 20
point p1 30 -20
circ2d3Tan tan1 c1 c2 p1

checklength tan1_1 -l 125.6637061435916
checklength tan1_2 -l 376.99111854338514
checklength tan1_3 -l 376.99111854338514