Answer:
4a^2 (8a+3)
Step-by-step explanation: it’s right
Answer:
Step-by-step explanation:
Volume of tank is 3000L.
Mass of salt is 15kg
Input rate of water is 30L/min
dV/dt=30L/min
Let y(t) be the amount of salt at any time
Then,
dy/dt = input rate - output rate.
The input rate is zero since only water is added and not salt solution
Now, output rate.
Concentrate on of the salt in the tank at any time (t) is given as
Since it holds initially holds 3000L of brine then the mass to volume rate is y(t)/3000
dy/dt= dV/dt × dM/dV
dy/dt=30×y/3000
dy/dt=y/100
Applying variable separation to solve the ODE
1/y dy=0.01dt
Integrate both side
∫ 1/y dy = ∫ 0.01dt
In(y)= 0.01t + A, .A is constant
Take exponential of both side
y=exp(0.01t+A)
y=exp(0.01t)exp(A)
exp(A) is another constant let say C
y(t)=Cexp(0.01t)
The initial condition given
At t=0 y=15kg
15=Cexp(0)
Therefore, C=15
Then, the solution becomes
y(t) = 15exp(0.01t)
At any time that is the mass.
Only one because there is one variable and the combined coefficients of x are non-zero.
(0.75(x+40)=0.70(x+20), 0.05x=14-30=-16, x=-320)
I think its B I`m not sure
The expression for the cost of the ABC Book Club is 2x + 40. The expression for the cost of the Easy Book Club is 3x + 35. To find when the total charge for both book clubs is equal, the two expressions must equal each other. (x = the number of books read)
2x + 40 = 3x + 35
Subtract 35 from both sides.
2x + 5 = 3x
Subtract 2x from both sides.
5 = x
So, the total charge for each club is equal when 5 books are read.
