![](data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 72 71" width="72"></svg>)
The distance between the two places is 360 km. Car a starts from place a and goes to place B, driving 72 km per hour. 25 minutes after car a starts, car B starts from place B and goes to place a, driving 48 km per hour. After the two cars meet, they continue to drive at the speed of their own will. Then the distance between the two cars is 120 km. How long does it take car a to start Solving the equation
Shea has been away for X hours,
72x+48（x-25/60）=360+120
120x=500
X = 25 / 6 hours
That is, X set out for 4 hours and 10 minutes
RELATED INFORMATIONS
- 1. Car a and car B leave 368 kilometers away from each other. When they meet, the ratio of the distance traveled by car a to that traveled by car B is 9:7, and car a and car B have more than two rows Using equation and proportional solution
- 2. The fruit supermarket transported 400 kg pears and 12 baskets of apples, 112 kg more than apples, how many kg per basket of apples on average
- 3. Can direct coupled amplifier amplify AC signal? Why?
- 4. Childhood fun, to be with mom and dad in childhood fun Within 100 words
- 5. Does "every boys and every girls" have this usage? If so, do you use the singular or plural as the subject predicate verb? I know each is singular
- 6. How many boats did you hire? How many students did you have?
- 7. It is proved that f (x) = √ (x ^ + 1) - x is a decreasing function in the domain of definition
- 8. How to prepare for the party
- 9. 1949∧2—1950∧2+1951∧2—1952∧2+…… +1997∧2—1998∧2
- 10. N and V after English words
- 11. What are the general components of bridge construction
- 12. A truck drives from place a to place B at the speed of 30km / h. one hour after starting, a car also drives from place a to place B at the speed of 50km / h. it arrives at place B half an hour earlier than the truck. Find the distance between a and B
- 13. At the same time, passenger cars and freight cars depart from two places 720 km apart and meet each other in six hours. The speed ratio of passenger cars and freight cars is 7:5. How much does freight car travel per hour?
- 14. It is known that the function f (x) is an odd function over the domain R. when x > = 0, f (x) = 2 ^ x + 2x + m (M is a constant), what is the value of F (- 1) A. - 3 B. - 1 C.1 D.3 I have to - 4-m. what about M? The answers are all constants
- 15. Let the domain of definition of function f (x) be r, and there are two propositions as follows: 1. If there is a constant m such that any x ∈ R, there is f (x) 2. If there exists x0 ∈ R, such that for any x ∈ R, and X is not equal to x0, f (x)
- 16. Let f (x) be defined as D. if there is a non-zero real number m such that for any x ∈ m (M is contained in D), there is (x-m) ∈ D and f (x-m) ≤ f (x), then F (x) is a low-key function of degree m on M. if f (x) whose domain is R is an odd function, when x ≥ 0, f (x) = | X - A ^ 2 | - A ^ 2, and f (x) is a low-key function of degree 5 on R, then the value range of real number a is?
- 17. If the function f (x) is a monotone function over the domain D, and there exists an interval [a, b] &; D (where a < b), such that when x ∈ [a, b], the value range of F (x) is exactly [a, b], then the function f (x) is said to be a positive function over D, and the interval [a, b] is called an equal domain interval (1) Given that f (x) = x 12 is a positive function on [0, + ∞), find the equal domain interval of F (x); (2) Try to explore whether there is a real number m, so that the function g (x) = x2 + m is a positive function on (- ∞, 0). If there is, ask for the value range of the real number m; if not, please explain the reason
- 18. Given that the definition field of function f (x) = √ (m-1) x ^ 2 + 2 (m-1) x + 3 is real number set R, the value range of real number m is obtained
- 19. Given that the domain of the function f (x) = √ MX2 + 4x + 4 is a set of real numbers, the value range of the real number m is obtained
- 20. If the function f (x) = MX / 4x-3 (x is not equal to 3 / 4) has f {f (x)} = x in the domain of definition, then M=