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The two trains are both 180 meters long. If the two trains run in opposite directions, it will take 12 seconds from the front to the trunk. If they run in the same direction, it will take 60 seconds from the front of a to the rear of B until the rear of a exceeds the front of B. assuming that the speed of a and B is constant, calculate the respective speed of the two trains
Let the speed of train a be x and that of train B be y
For example, when two cars are traveling in opposite directions, it takes 12 seconds from the front of the car to the rear of the car. The equation is as follows: (x + y) 12 = 180 + 180
If it takes 60 seconds from the front of car a to the rear of car B to the front of car B, the equation (X-Y) 60 = 180 + 180
Solve the binary linear equations: x = 18 m / s, y = 12 m / s
Each train is 180 meters long. If the two trains run in opposite directions, it takes 12 seconds from the front of the train to the rear of the train. If the two trains run in the same direction, it takes 60 seconds from the front of the train to the rear of the train until the rear of the train exceeds the front of the train. Assuming that the speed of the train remains unchanged, the speed of the two trains is calculated
It's a linear equation with one variable!
Let car a be x meters per second, then car B be [(180 + 180) - 12x] / 12 meters per second
60{x-[（180+180）-12x]÷12}=180*2
60x-1800+60x=180*2
120x=1440
x=12
[(180 + 180) - 12 * 12] △ 12 = 18 m / S
A: car B is 18 meters per second
Two cars are side by side on the straight road. A person in the car can see the trees moving eastward outside the window. B has a person in the car
Is a and B moving westward at the same speed at the same time?
Your topic is not complete, known a see tree move eastward, can only draw a car move westward
There are several cases,
Both a and B move westward, but the speed can be the same or different
2. A moves westward and B moves eastward, but the speed can be the same or different
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