$試問坐標平面上共有幾條直線，\;會使得點O(0,0)到此直線之距離為1，且點A(3,0)到此直線之距離為2?   $
$(1)\; 1條 \; (2)\; 2條\;(3)\; 3條\;(4)\; 4條\; (5)\;無窮多條\;  [98學科能力測驗]$

$O$

$A$

Show Tangent Line

O = (0, 0)
A = (3, 0)
a_1 = 1
B = Point(Circle[O, 1])
a = Segment(O, B)
b_1 = 2
C = Point(Circle[A, 2])
b = Segment(A, C)
c = Circle(O, B)
d = Circle(A, C)
e, f, g = Tangent(d, c)
h = false