Respuesta :
Answer:
a=8 and b=1
Step-by-step explanation:
Given : Sun, a kayaker, paddles 8 miles upstream (against the current) in 2 hours. Returning to her original location, she paddles downstream (with the current) the same distance in 1 hour. The equations represent x, the paddling speed, and y, the speed of the current.
[tex]2(x - y) = a[/tex] and [tex]b(x + y) = 8[/tex]
To find : Which are true?
Solution :
If x represents the paddling speed, and y represents the speed of the current.
The relative speed in upstream is x-y
Relative time in downstream= x+y
A kayaker, paddles 8 miles upstream (against the current) in 2 hours.
[tex]\text{Distance}=\text{Speed} \times \text{Time}[/tex]
[tex]8=(x-y)\times 2[/tex]
Comparing with [tex]2(x - y) = a[/tex]
We get, a=8
Returning to her original location, she paddles downstream (with the current) the same distance in 1 hour.
[tex]\text{Distance}=\text{Speed} \times \text{Time}[/tex]
[tex]8=(x+y)\times 1[/tex]
Comparing with [tex]b(x + y) = 8[/tex]
We get, b=1
Thus, a=8 and b=1
Therefore, Option 1 and 4 is correct.
