Question 900323
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Hi
52/(r+5) + 52/(r-5) = 13/3
 52(r-5) + 52(r+5) = 13/3(r^2 - 25)
  104r = (13/3)(r^2-25)
  13r^2 -312r - 13*25 = 0
 r^2 - 24r - 25 = 0 
(r +1)(r-25) = 0,  r = 25mph