The differential equation that has the given slope is: dy/dx = -xy.
<h3>How to find the differential equation that models the situation?</h3>
We have to look at the slope, given in the graph of the solution of the differential equation, and represented by dy/dx. From the graph, we have that:
- In quadrants I and III, in which x and y have the same signal, the differential equation is decreasing, hence the slope is negative.
- In quadrants II and IV, in which x and y have different signals the differential equation is increasing, hence the slope is positive.
The differential equation that is negative when x and y have the same signals and positive when they do not have is given by the following option:
dy/dx = -xy.
More can be learned about differential equations at brainly.com/question/14423176
#SPJ1
Answer:
A(t) = amount remaining in t years
= A0ekt, where A0 is the initial amount and k is a constant to be determined.
Since A(1690) = (1/2)A0 and A0 = 80,
we have 40 = 80e1690k
1/2 = e1690k
ln(1/2) = 1690k
k = -0.0004
So, A(t) = 80e-0.0004t
Therefore, A(430) = 80e-0.0004(430)
= 80e-0.172
≈ 67.4 g
Step-by-step explanation:
There will be 38 grams remaining.
The equation would be of the form
y = a(1+r)ˣ, where a is the initial value, r is the rate as a decimal number, and x is the amount of time. Using our values from the problem, we have:
y = 670(1-0.273)^9 = 670(0.727)^9 = 38
First, make up some variables to represent the number of Girls and Boys in the choir.
B = number of boys
G = number of girls
You know that there are 4 times as many girls in the choir as boys. Therefore, the equation you can write is:

If you cross-multiply, then you get the simplified equation:
G = 4B
Intuitively this makes sense since if you multiplied the number of boys in the class by 4, that would be equal to the number of girls you have.
Now, we know that the total class size is 60. So girls plus boys equals 60:
G+B = 60
To solve the equation, replace the G in this equation with the replacement you found before, 4B.
G + B = 60 -->
4B + B = 60 -->
5B = 60 -->
B = 12
However, you are trying to find the number of girls, so plug the answer back into your equation.
G + B = 60 -->
G + 12 = 60 -->
G + 12 -12 = 60 - 12 -->
G = 48
The number of girls you have is 48.