Answer:
Step-by-step explanation:
This is a differential equation problem most easily solved with an exponential decay equation of the form
. We know that the initial amount of salt in the tank is 28 pounds, so
C = 28. Now we just need to find k.
The concentration of salt changes as the pure water flows in and the salt water flows out. So the change in concentration, where y is the concentration of salt in the tank, is
. Thus, the change in the concentration of salt is found in
inflow of salt - outflow of salt
Pure water, what is flowing into the tank, has no salt in it at all; and since we don't know how much salt is leaving (our unknown, basically), the outflow at 3 gal/min is 3 times the amount of salt leaving out of the 400 gallons of salt water at time t:

Therefore,
or just
and in terms of time,

Thus, our equation is
and filling in 16 for the number of minutes in t:
y = 24.834 pounds of salt
Answer:
9^4 is what you’re looking for right?
Step-by-step explanation:
18=3+36x-50x-55
18=3-14x-55
18=-14x-52
70=-14x
x=-5
Answer:
m = 11
Step-by-step explanation:
Given
(m + 4) = 6 ← multiply both sides by 5 to clear the fraction
2(m + 4) = 30 ( divide both sides by 2 )
m + 4 = 15 ( subtract 4 from both sides )
m = 11
This method avoids having to deal with awkward fractions
Answer:
x=1
Step-by-step explanation:
For algebra always start by rewriting it.
4+x+2-2x=5
Then ask yourself is there any like terms we can combine, and here yes there is. 4 and 2 and x and -2x. Now lets combine them and rewrite.
6-x=5
Now lets get x alone and the quickest way is to subtract 6 to the other side
6-x=5
-6 -6
-x=-1
Now the two negatives cancel out as you would divide both sides by the coefficient -1 to get positive x alone. We can make this easier by just canceling out the negatives.
Your answer is
x=1