SOLUTION: A car traveling at a uniform speed reached its destination 400 kilometers away from the city. On the return trip, because of motor trouble, the speed was reduced by 10 kilometers p

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Question 1187410: A car traveling at a uniform speed reached its destination 400 kilometers away from the city. On the return trip, because of motor trouble, the speed was reduced by 10 kilometers per hour causing the car to stay on the road 2 hours longer. Find the following:
a. speed of the car going to its destination and;
b. speed on its return trip

Answer by ikleyn(52784) About Me  (Show Source):
You can put this solution on YOUR website!
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A car traveling at a uniform speed reached its destination 400 kilometers away from the city.
On the return trip, because of motor trouble, the speed was reduced by 10 kilometers per hour
causing the car to stay on the road 2 hours longer. Find the following:
a. speed of the car going to its destination and;
b. speed on its return trip
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x = the speed to the destination, in km/h.

Then the speed returning back is x-10  km/h.


Write the "time" equation


    400%2F%28x-10%29 - 400%2Fx = 2  hours.


Reduce it to a quadratic equation and solve using the quadratic formula or factoring.


ANSWER.  The speed was 50 km/h to the destination and 40 km/h back.

Solved.