Answer:
c
Step-by-step explanation:
but it does depend on how long the journey is
Answer:
The answer to your question is 20x + 21y + 14
Step-by-step explanation:
Data
Expression 1/5 (150x - 80y + 50 - 50x - 25y + 20)
Process
1.- Multiply 1/5 by each term
150/5x - 80/5y + 50/5 - 50/5x - 25/5y + 20/5
2.- Simplify
30x - 16y + 10 - 10x - 5y + 4
3.- Simplify like terms
(30x - 10x) + (-16y - 5y) + (10 + 4)
4.- Result
20x + 21y + 14
Answer:
dy/dt = 7y / (t − 1000)
Step-by-step explanation:
Change in mass of salt = mass of salt going in − mass of salt going out
dy/dt = 0 − (C kg/L × 7 L/min)
where C is the concentration of salt in the tank.
The concentration is mass divided by volume:
C = y / V
The volume in the tank as a function of time is:
V = 1000 + 6t − 7t
V = 1000 − t
Therefore:
C = y / (1000 − t)
Substituting:
dy/dt = -7y / (1000 − t)
dy/dt = 7y / (t − 1000)
If we wanted, we could separate the variables and integrate. But the problem only asks that we find the differential equation, so here's the answer.
The equation is y = -4x - 2. the equation will be in the form y = mx + b because this is a linear equation. the m is the slope, and this can be found by counting the units between points as rise over run. you can use the first and second points to do this. the rise is -4, and the run is 1, so the slope is -4. the third point is the y-intercept and that is where you find the b value. the coordinates are (0, -2), so the b value is -2.
