Answer:
a) 
b) 
Step-by-step explanation:
By definition, we have that the change rate of salt in the tank is
, where
is the rate of salt entering and
is the rate of salt going outside.
Then we have,
, and

So we obtain.
, then
, and using the integrating factor
, therefore
, we get
, after integrating both sides
, therefore
, to find
we know that the tank initially contains a salt concentration of 10 g/L, that means the initial conditions
, so 

Finally we can write an expression for the amount of salt in the tank at any time t, it is 
b) The tank will overflow due Rin>Rout, at a rate of
, due we have 500 L to overflow
, so we can evualuate the expression of a)
, is the salt concentration when the tank overflows
Answer:
14x + 14
Step-by-step explanation:
Perimeter = 2( L + W)
2(2x+7 + 5x) = 2(7x + 7)
distributive property
= 14x + 14
Answer:
Natalie bought 500 apples at $0.40 each, then she pays $0.40 500 times, this means that the total cost of the 500 apples is:
Cost = 500*$0.40 = $200
Now she threw away n apples from the 500 apples, then the number of apples that she has now is:
apples = 500 - n
And she sells the remaining apples for $0.70 each.
a) The amount that she gets by selling the apples is:
Revenue = (500 - n)*$0.70
b) We know that she did not make a loss, then the revenue must be larger than the cost, this means that:
cost ≤ revenue
$200 ≤ (500 - n)*$0.70
c) We need to solve the inequality for n.
$200 ≤ (500 - n)*$0.70
$200/$0.70 ≤ (500 - n)
285.7 ≤ 500 - n
n + 285.7 ≤ 500
n ≤ 500 - 285.7
n ≤ 214.3
Then the maximum value of n must be equal or smaller than 214.3
And n is a whole number, then we can conclude that the maximum number of rotten apples can be 214.
The equation 11x + 10y = 32 is a linear equation, and the solution to the linear equation 11x + 10y = 32 is 
<h3>How to solve the equation?</h3>
The equation is given as:
11x + 10y = 32
Subtract 11x from both sides
10y = 32 - 11x
Divide both sides by 10

Hence, the solution to the linear equation 11x + 10y = 32 is 
Read more about linear equations at:
brainly.com/question/14323743
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