The distancce travelled = 360 km.
Let the speed of the train = x kmph.
x2 + 5x =
x2 + 5x - = 0
x2 + 45x - x - = 0
x(x + 45) - (x + 45)
(x + 45)(x - ) = 0
x + 45 = 0 or x - = 0
x = -45 or x =
But x can't be negative.
∴ The speed of the train = kmph.