Answer:
-2
Step-by-step explanation:
3(a+1.5)=-1.5
a+1.5 = - 1.5/3 = - 0.5
a = - 0.5 - 1.5 = - 2
<h3>
Answer: 80 meters</h3>
This is an isosceles triangle. The dashed line is the height which is perpendicular to the base 120. The height is always perpendicular to the base. The dashed line cuts the base into two equal pieces (this only works for isosceles triangles when you cut at the vertex like this).
So we have two smaller triangles each with a base of 60 and a height of x. Focus on one of the right triangles and use the pythagorean theorem to solve for x.
a^2 + b^2 = c^2
x^2 + (60)^2 = (100)^2
x^2 + 3600 = 10000
x^2 = 10000 - 3600
x^2 = 6400
x = sqrt(6400)
x = 80
Each smaller right triangle has side lengths of 60, 80, 100
Note the ratio 60:80:100 reduces to 3:4:5. A 3-4-5 right triangle is a very common pythagorean primitive.
Answer:
![\frac{dP}{dt} = rP(1 - \frac{P}{K}) = 0.017P(1 - \frac{P}{16})](https://tex.z-dn.net/?f=%5Cfrac%7BdP%7D%7Bdt%7D%20%3D%20rP%281%20-%20%5Cfrac%7BP%7D%7BK%7D%29%20%3D%200.017P%281%20-%20%5Cfrac%7BP%7D%7B16%7D%29)
Step-by-step explanation:
The logistic function of population growth, that is, the solution of the differential equation is as follows:
![P(t) = \frac{KP_{0}e^{rt}}{K + P_{0}(e^{rt} - 1)}](https://tex.z-dn.net/?f=P%28t%29%20%3D%20%5Cfrac%7BKP_%7B0%7De%5E%7Brt%7D%7D%7BK%20%2B%20P_%7B0%7D%28e%5E%7Brt%7D%20-%201%29%7D)
We use this equation to find the value of r.
In this problem, we have that:
![K = 16, P_{0} = 2, P(50) = 4](https://tex.z-dn.net/?f=K%20%3D%2016%2C%20P_%7B0%7D%20%3D%202%2C%20P%2850%29%20%3D%204)
So we find the value of r.
![P(t) = \frac{KP_{0}e^{rt}}{K + P_{0}(e^{rt} - 1)}](https://tex.z-dn.net/?f=P%28t%29%20%3D%20%5Cfrac%7BKP_%7B0%7De%5E%7Brt%7D%7D%7BK%20%2B%20P_%7B0%7D%28e%5E%7Brt%7D%20-%201%29%7D)
![4 = \frac{16*2e^{50r}}{16 + 2*(e^{50r} - 1)}](https://tex.z-dn.net/?f=4%20%3D%20%5Cfrac%7B16%2A2e%5E%7B50r%7D%7D%7B16%20%2B%202%2A%28e%5E%7B50r%7D%20-%201%29%7D)
![4 = \frac{32e^{50r}}{14 + 2e^{50r}}](https://tex.z-dn.net/?f=4%20%3D%20%5Cfrac%7B32e%5E%7B50r%7D%7D%7B14%20%2B%202e%5E%7B50r%7D%7D)
![56 + 8e^{50r} = 32e^{50r}}](https://tex.z-dn.net/?f=56%20%2B%208e%5E%7B50r%7D%20%3D%2032e%5E%7B50r%7D%7D)
![24e^{50r} = 56](https://tex.z-dn.net/?f=24e%5E%7B50r%7D%20%3D%2056)
![e^{50r} = 2.33](https://tex.z-dn.net/?f=e%5E%7B50r%7D%20%3D%202.33)
Applying ln to both sides of the equality
![50r = 0.8459](https://tex.z-dn.net/?f=50r%20%3D%200.8459)
![r = 0.017](https://tex.z-dn.net/?f=r%20%3D%200.017)
So
The differential equation is
![\frac{dP}{dt} = rP(1 - \frac{P}{K}) = 0.017P(1 - \frac{P}{16})](https://tex.z-dn.net/?f=%5Cfrac%7BdP%7D%7Bdt%7D%20%3D%20rP%281%20-%20%5Cfrac%7BP%7D%7BK%7D%29%20%3D%200.017P%281%20-%20%5Cfrac%7BP%7D%7B16%7D%29)