A train travels a distance of 480 km at a uniform speed. If the speed had been 8 km/h less, then it would have taken 3 hours more to cover the same distance. We need to find the speed of the train.
x2 – 3x – 10 = 0
⇒ x2 – 5x + 2x– 10 = 0
⇒ x(x – 5) + 2(x – 5) =0
⇒ (x – 5) (x + 2) = 0
⇒ x–5 = 0 or x + 2 = 0
x = 5 or x = –2
Hence, the roots of the given quadratic equation are 5 and (-2).