You must calculate how many ways can 2 people be selected from 65.
The formula is:
n! / r! * (n-r)! =
65! / 2! * 63! =
65*64*63! / 2 * 63! =
65*64 / 2 =
2,080 handshakes
Source:
http://www.1728.org/combinat.htm
<span>x^2 + 15x + 56.25 = 105.25
"Completing the square" is one of many different techniques for solving a quadratic equation. What you do is add a constant to both sides of the equation such that the lefthand side can be factored into the form a(x+d)^2. For instance, squaring (X+D) = X^2 + 2DX + D^2. Notice the 2DX term. That is the same term as the 15x term in the problem. So 2D = 15, D = 7.5. And D^2 = 7.5^2 = 56.25.
So we have
x^2 + 15x + 56.25 = 49 + 56.25
Which is
x^2 + 15x + 56.25 = 105.25
Which is the answer desired.
Now the rest of this is going beyond the answer. Namely, it's answering the question "Why does complementing the square help?"
Well, we know that the left hand side of the equation can now be written as
(x+7.5)^2 = 105.25
Now take the square root of each side
(x+7.5) = sqrt(105.25)
And let's use both the positive and negative square roots.
So
x+7.5 = 10.25914226
and
x+7.5 = -10.25914226
And let's find X.
x+7.5 = 10.25914226
x = 2.759142264
x+7.5 = -10.25914226
x = -17.75914226
So the roots for x^2 + 15x - 49 is 2.759142264, and -17.75914226</span>
polynomial of the 5th degree, with two terms.
Distribute 4x^2(–2x^2 + 5x^3) to get –8x^2 + 20x^5. Reorder in standard form 20x^5-8x^4. 5 is the highest exponent so it is the 5th degree, there are two terms because terms are separated by a plus or minus.
Answer:
1/2
Step-by-step explanation:
A sample space is a collection or a set of possible outcomes of a random experiment.
I have created the sample space for these data and attached it. As you can see there are 16 possible outcomes.
To find the probability that the total showing is greater than 9, simply identify the number of values in the sample space that are greater than 9.
(I have highlighted these in yellow).
Therefore, P(X>9) = 8/16 = 1/2
