Using Quadratic Formula to solve Quadratic Equations
8. A train travels 360 km at a uniform speed. If, the speed had been 5 km/hr more, it would have taken 1 hour less for the same journey. Find the speed of the train.
Let the speed of the train = x km/hr
If, speed had been 5km/hr more, train would have taken 1 hour less. So, according to this condition, we have
Comparing equation with general equation , we get
Applying quadratic formula to solve equation, we get
Speed of train cannot be in negative. Therefore, we discard
Therefore, speed of train = 40 km/hr