Carcass wrote:

If points A, B, and C are the centers of the above circles and the circles have radii of 2,3, and 4 respectively, what is the perimeter of triangle ABC ?
A. 9
B. 3π
C. 12
D. 18
E. 9π
Let's add a point at each of the three points where two circles touch
Since the radius of the smallest circle is
2, we can add that to our diagram to get:

When we do the same for the other two circles we get:

So, the perimeter of triangle ABC =
2 +
2 +
3 +
3 +
4 +
4 = 18
Answer: D
Cheers,
Brent