% This figure was an illustration for an exercice about
% homothecies.
% Copyright (c) Christian Obrecht 2001

frame(-4,-2.5,7,2.5,.8)

c1 = circle(point(0,0),2)
c2 = circle(point(3.5,0),1.5)
O = point(2,0)
l1 = line(O,15:) ; l2 = line(O,-30:)
A O intersection(l1,c1)
O B intersection(l1,c2)
C O intersection(l2,c1)
O D intersection(l2,c2)

draw(c1) ; draw(c2) ; draw(l1) ; draw(l2)
draw("$C_1$",point(c1,180:),180:)
draw("$C_2$",point(c2,0:),0:)
draw("$D_1$",abscissa(l1,-3),135:)
draw("$D_2$",abscissa(l2,6),45:)
draw("$A$",A,-120:) ; draw("$B$",B,60:)
draw("$C$",C,90:) ; draw("$D$",D,-90:)
draw("$O$",O,.4,-135:)