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Find the radius of the circle of intersection between the two spheres ...?
First sphere centered at (1,1,1) and has a radius of 10
Second sphere centered at (5, 7, 13) and has a radius of 8.
2 Answers
- PopeLv 77 years ago
Let the centers be A(1, 1, 1) and B(5, 7, 13), and let P be any point of intersection.
In triangle ABP,
AB = 14
BP = 8,
PA = 10
area(ABP) = 16√(6) ... by Heron's formula
Let Q be the foot of the altitude from P.
area(ABP) = (AB)(PQ)/2
(14)PQ/2 = 16√(6)
PQ = 16√(6)/7
radius of circle of intersection = 16√(6)/7