Answer:

Step-by-step explanation:
Given;
x² - 2x - 1 = 0
Solve by completing the square method;
⇒ take the constant to the right hand side of the equation.
x² - 2x = 1
⇒ take half of coefficient of x = ¹/₂ x -2 = -1
⇒ square half of coefficient of x and add it to the both sides of the equation


⇒ take the square root of both sides;

Therefore, option B is the right solution.
Answer:

And using the probability mass function we got:
Step-by-step explanation:
Let X the random variable of interest, on this case we now that:
The probability mass function for the Binomial distribution is given as:
Where (nCx) means combinatory and it's given by this formula:
And we want to find the following probability:

And using the probability mass function we got:
Answer:
-3x^4 - 14x^3 + 3x^2 - 10
Step-by-step explanation:
Answer:
R=-13
Step-by-step explanation:
S=-1-r/5-2
4=-1-r/3
Cross multiply
4*3=-1-r
12=-1-r
Collect like terms
12+1=-r
-r=13
Divide both sides by -
r=-13