qcircle c1 0 120 20
qline l1 0 0 10 20
qline l2 0 0 10 -40
circ2d3Tan tan1 c1 l1 l2

checklength tan1_1 -l 461.86006847878718
checklength tan1_2 -l 163.75801021417183
checklength tan1_3 -l 321.80336707682847
checklength tan1_4 -l 235.02950419226329