Question 424511
 The ellipse used has a major axis of 12 ft and a minor axis of 5 ft. 
a) How far from the center are the foci?
b) How far from the lithotripter is the patient's kidney?
c) Write an equation for the ellipse used. 
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a^2 = 12^2 = 144
b^2 = 5^2 = 25
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a^2 = b^2 + c^2
c = sqrt(144-25)
c = sqrt(119)
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Focus distance from center = sqrt(119) ft
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Cheers,
Stan H.
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