10th grade Academic Math
posted by Neil .
hi can you help me with this problem please, thank you.
If the speed of an experimental car is decreased by 8km/h it completes a 140 km trip in 2 hours more than had it been traveling at its usual speed. Determine its usual speed.

Neil,
You have posted the same question three times in less than 50 minutes probably without even noticing that the previous questions have been answered.
If you do not understand the answer, or if you need more information, you should post a followup question instead of posting the same question again. Another teacher might answer the question over again and that slows the answering process.
Thanks for your understanding.