Since my other thread is lacking attention, perhaps it is more suitable here:
I inserted some fixed constants and multiplied out
(48/.5)(1-^e-.5t)(sin 45) + (9.8/.25)(1-(.5t) - e^-.5t) = 0
(96 - 96e^-.5t)(sin 45) + 39.2(1-(.5t)-e^-.5t) = 0
67.88 - 67.88^e-.5t + 39.2 - 19.6t -...