To solve this problem you must apply the proccedure shown below:
1. The vertex i at <span>(0, 36) and a focus at (0, 39), then you have:
a=36
a^2=1296
2. The directrix is:
y=a^2=c
c=39
y=1296/39
</span>y=432/13<span>
Therefore, the answer is the option D, which is: </span><span>D. y=± 432/13</span>
The answer is B.
The formula for arc length is s = r(theta) Theta must be in radians, so convert 40 degrees to radians, which is 2pi/9. Multiply 2pi/9 by the radius, 9, and then you'll get the answer. Hopes this helps!
Answer:
Part 1: There are 4.7*10^21 ways to select 40 volunteers in subgroups of 10
Part 2: The research board can be chosen in 32760 ways
Step-by-step explanation:
Part 1:
The number of ways in which we can organized n elements into k groups with size n1, n2,...nk is calculate as:

So, in this case we can form 4 subgroups with 10 participants each one, replacing the values of:
- n by 40 participants
- k by 4 groups
- n1, n2, n3 and n4 by 10 participants of every subgroups
We get:

Part 2:
The number of ways in which we can choose k element for a group of n elements and the order in which they are chose matters is calculate with permutation as:

So in this case there are 4 offices in the research board, those are director, assistant director, quality control analyst and correspondent. Additionally this 4 offices are going to choose from a group of 5 doctors.
Therefore, replacing values of:
- n by 15 doctors
- k by 4 offices
We get:

Answer:
For this case, the first thing we must do is define variables:
x: number of hammers
y: number of wrenches
We write the system of inequations:
10x + 6y <= 120
x + y> = 14
Step-by-step explanation: