F :: Point of Intersection
Time Limit: 1 Second Memory Limit: 32768 KB
Given two circles on the same plane which are centered at (x1,y1) and (x2,y2) ,with radiuses r1 and r2, respectively.We can see that they have two common tangent lines in most of the cases.Now you are asked to write a programme to calculate the point of intersection of the two tangents if there exists one. ( See Figure 1 )
Figure. 1 Point of intersection
Input
The input data consists of the information of several figures.The first line
of the input contains the number of figures.
Each figure is described by two lines of data.Each line contains 3 integers
constituting the coordinates of the center (x, y) and the radius r (>0) of
a circle.
Output
For each figure, you are supposed to output the coordinates (x, y) of the point
of intersection if it exists.The x and y must be rounded to two decimal places
and be separated by one space.If there is no such point exists simply output
"Impossible."
Sample Input
2 0 0 10 0 0 5 0 0 10 10 0 1
Sample Output
Impossible. 11.11 0.00Submit
Source: Zhejiang University Local Contest 2002, Preliminary