Answer:the length of time he spent running is 8 minutes.
the length of time he spent swimming is 15 minutes.
Step-by-step explanation:
Let x represent the length of time he spent running.
Let y represent the length of time he spent swimming.
He exercised for a total of 23 minutes. This means that
x + y = 23
When running he burns 35 calories per minute, and when he swims he burns 30 calories per minute. He has burned 730 calories after exercising. It means that
35x + 30y = 730 - - - - - - - - - -1
Substituting x = 23 - y into equation 1, it becomes
35(23 - y) + 30y = 730
805 - 35y + 30y = 730
- 35y + 30y = 730 - 805
- 5y = - 75
y = - 75/ -5
y = 15
Substituting y = 15 into x = 23 - y, it becomes
x = 23 - 15 = 8
Answer:
2.5 hours
Step-by-step explanation:
We are given that
Original height of candle=5 in
Every hour candle loses =8% of 5 in=0.4
According to question
![5-0.4x>4](https://tex.z-dn.net/?f=5-0.4x%3E4)
Subtract 4 from both sides we get
![5-4-0.4x>0](https://tex.z-dn.net/?f=5-4-0.4x%3E0)
![1-0.4x>0](https://tex.z-dn.net/?f=1-0.4x%3E0)
![-0.4x>-1](https://tex.z-dn.net/?f=-0.4x%3E-1)
![0.4x](https://tex.z-dn.net/?f=0.4x%3C1)
Divide by 0.4 on both sides
![x](https://tex.z-dn.net/?f=x%3C%5Cfrac%7B1%7D%7B0.4%7D)
![x](https://tex.z-dn.net/?f=x%3C2.5)
x=2.5 hours
Until the candle has been burning for at least 2.5 hours, the height of her candle will be more than four inches.
Answer:
..........
Step-by-step explanation:
.......hey :)
What to do with these equations ?
Answer:
were is tha problem
Step-by-step explanation: