Answer: 
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Explanation:
We cannot have negative numbers under the square root, if we wanted the result to be some real number.
The stuff under the square root must be 0 or larger.
This means the x+2 must be 0 or larger.

Similarly, the 5-x must be 0 or larger. But wait, we cannot have 0 in the denominator (or else we have a division by zero error), so 5-x must be larger than 0.
5-x > 0
5-x+x > 0+x
5+0 > 0+x
5 > x
x < 5
Combine both
and
to find the domain is 
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Visual confirmation is shown below. I used Desmos which is a free graphing app.
- f(x) = sqrt(x+2) is in red
- g(x) = sqrt(5-x) is in blue
- h(x) = f(x)/g(x) is in green
The green curve is what we're after. It's between x = -2 and x = 5
We include -2, but exclude 5.
Take note of the closed endpoint at x = -2, and also the vertical asymptote at x = 5. The curve approaches this asymptote but never actually touches it. Think of an electric fence you can get closer to, but not actually touch.
You would have to get 56 points everyday.
If you subtract 1300 from 1580 you get 280. divide 280/5 which equals 56.
56*5=280
280+1300=1580.
56 is the amount of points you need
Just create a problem and figure it out.
Let's say the original diameter is 4. This means the radius is 4/2 = 2.
A = 2πr^2
A = 2π(2)^2
A = 2π(4)
A = 8π
The new diameter is 50% larger than the original.
50% of 4 is 2. 2 + 4 = 6. So the new diameter is 6. The radius is 6/2 = 3.
A = 2πr^2
A = 2π(3)^2
A = 2π(9)
A = 18π
Old area was 8π, new area is 18π. Now divide the difference from the original area:
18π - 8π = 10π
10π/8π = 1.25 * 100 = 125%
To solve this problem you must apply the proccedure shown below:
1. You have to find the distance from the center to the focus, as below:
c=√(a^2-b^2)
Where a is the major radius and b is the minor radius.
2. Therefore, by the graph, you have:
a=6
a^2=36
b=3
b^2=9
3. When you substitute the values, you obtain:
c=5.2
4. As you can see in the graph, the coordinates of the center is (3,4), then, the locations of the foci:
3+c=8.2
3-c=-2.2
The answer is: (-2.2,4) and (8.2,4)