3/4 + 5/16
=12/16 +5/16
=17/16
=1 1/16
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:
x = 4
Step-by-step explanation:
we know that 72 and (2x + 10) add up to 90
90-72 = 18
(2x + 10) = 18
2x = 8
x = 4
Answer:
slope:3
y intercept:1
equation:y=3x+1
Step-by-step explanation:
<span>Selection A is correct</span>