Math Is Fun Forum

Let ABCDEFGH be a rectangular prism where AB = 2, AD = 3, and AE = 5. Find the volume of pyramid ACFH.

Can you please help me on how to find the base area of the pyramid?

Each of the three circles in the figure below is externally tangent to the other two, and each side of the triangle is tangent to two of the circles. If each circle has radius three, then find the perimeter of the triangle.

[asy]
unitsize(0.5 cm);

draw(Circle(dir(90),sqrt(3)/2));
draw(Circle(dir(90 + 120),sqrt(3)/2));
draw(Circle(dir(90 + 240),sqrt(3)/2));
draw((1 + sqrt(3))*dir(90)--(1 + sqrt(3))*dir(90 + 120)--(1 + sqrt(3))*dir(90 + 240)--cycle);
[/asy]