Two circles of radius 1 are centered at $(4,0)$ and $(-4,0).$ How many circles are tangent to both of the given circles and also pass through the point $(0,5)$?
Two circles of radius 1 are centered at (4,0) and (-4,0).
How many circles are tangent to both of the given circles and also pass through the point (0,5)?
answer see: https://web2.0calc.com/questions/a-circle-problem#r1
![]()
Hey heureka.....I understand how you got the equations for the first and last circles in your answer.....could you show how you got the equations for either (2) or (3) ????
![]()
Two circles of radius 1 are centered at (4,0) and (-4,0).
How many circles are tangent to both of the given circles and also pass through the point (0,5)?
A long time ago I wrote a program, see table, the calculation of the (Problem of Apollonius) I have derived by means of the vector calculation.
The third circle has the center (0, 5) and the radius 0.
1. Kreis: Mittelpunkt M1 und Radius r1: x1 = 4 y1 = 0 r1 = 1
2. Kreis: Mittelpunkt M2 und Radius r2: x2 = -4 y2 = 0 r2 = 1
3. Kreis: Mittelpunkt M3 und Radius r3: x3 = 0 y3 = 5 r3 = 0
\(\begin{array}{|c|l|c|c|c|} \hline & \text{Index } & x\text{ center} & y\text{ center}&r \text{ radius}\\ \hline 1&+++&0&1.66667&3.33333 \\ \hline 2 &&-8.88178e-16&1.66667&3.33333\\ \hline 3 &++-&0&1.66667&3.33333\\ \hline 4&&-8.88178e-16&1.66667&3.33333\\ \hline 5&+-+&-1.0328&1&4.13118\\ \hline 6&&-1.0328&1&4.13118\\ \hline 7&+--&-1.0328&1&4.13118\\ \hline 8&&-1.0328&1&4.13118\\ \hline 9&-++&1.0328&1&4.13118\\ \hline 10&&1.0328&1&4.13118\\ \hline 11&-+-&1.0328&1&4.13118\\ \hline 12&&1.0328&1&4.13118\\ \hline 13&--+&0&0&5\\ \hline 14&&0&0&5\\ \hline 15&---&0&0&5\\ \hline 16&&0&0&5\\ \hline \end{array}\)
![]()