S = d/t
st = d
t = d/s
The time going is t1.
The time returning is t2.
The total time is 4 hours, so we have t1 + t2 = 4
The speed of the current is c.
The speed going is 9 + c.
The speed returning is 9 - c.
t1 = 16/(9 + c)
t2 = 16/(9 - c)
t1 + t2 = 16/(9 + c) + 16/(9 - c)
4 = 16/(9 - c) + 16/(9 + c)
1 = 4/(9 - c) + 4/(9 + c)
(9 + c)(9 - c) = 4(9 - c) + 4(9 + c)
81 - c^2 = 36 - 4c + 36 + 4c
81 - c^2 = 72
c^2 = 9
c^2 - 9 = 0
(c + 3)(c - 3) = 0
c + 3 = 0 or c - 3 = 0
c = -3 or c = 3
We discard the negative answer, and we get c = 3.
The speed of the current is 3 mph.
Answer:
8
Step-by-step explanation:
multiply 40 x 20 which =80
then put a point after the 8 then add a 0.
Your final answer should be 40% of $20 is $8.00
12-4=e.8 not 10. I think you need to look at the question and look at what you wrote.
Answer:
Markers =53
crayons= 56
Step-by-step explanation:
When there's a problem ask
Because there are g(x)=√(x-1) +1 have √ and +1, the values of g(x) can be only positive.
Value under √ should be positive.
x-1≥0
x≥1.
Correct answer is A.