Hi
60(s+2) + 60(s-2) = 16(s+2)(s-2)
30(s+2) + 30(s-2) = 8(s+2)(s-2)
60s = 8(s^2 - 4)
8s^2 - 60s -32 = 0
2s^2 -15x - 8 = 0
(2s +1)(s -8) = 0 (Tossing out the negative solution for unit measure)
s = 8mph
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