Question 383768
substituting ___ (420 / t) + 10 = 420 / (t - 1)


multiplying by t(t-1) ___ 420t - 420 + 10t^2 - 10t = 420t


t^2 - t - 42 = 0


factoring ___ (t + 6)(t - 7) = 0


t + 6 = 0 ___ t = -6 , x = -70


t - 7 = 0 ___ t = 7 , x = 60