H2_pic3

import geometry;

size(9cm, 0);
defaultpen(fontsize(10pt));
dotfactor = 6;
point A,B,C,O,M,K;
real R=2;
O=origin; A=1.5R*dir(-15);
circle circ=circle(O, R);
line[] t= tangents(circ, A);
point[] Mp = intersectionpoints(circ, t[1]);
M=Mp[0];
point O1=point(circ, -0.25*length(circ));
K=projection(O,O1)*A;
point[] pcirc = intersectionpoints(circ, line(A,K));
B=pcirc[0];  C=pcirc[1];
markrightangle(size=0.3cm,B,K,O);

draw(A--(M+dir(A--M))^^A--C^^O--K^^O--B);

draw(circ, black+pt);

dot(O^^A^^M^^B^^C^^K);
label("$O$", O, N);
label("$A$", A, S);
label("$B$", B, SE);
label("$C$", C, SW);
label("$M$", M, NE);
label("$K$", K, S);
label(Label("$12$", Relative(0.5)), K--B);
label(Label("$12$", Relative(0.5)), C--K);
label(Label("$5$", Relative(0.5)), O--K);
label(Label("$8$", Relative(0.5)), B--A);
label(Label("$16$", Relative(0.5)), A--M);