Is the first one none of the above? Is the second one 0? Is the third one 6✓5-4✓7?

How do u stop whaching adds if ur new

Alexxx [7]

Answer:

to be honest I dont know

Step-by-step explanation:

I dont know how.

6 0

3 years ago

Read 2 more answers

A distribution of scores for a test of life stressors has a mean of µ = 125 and standard deviation of σ = 15. The researcher cal

laila [671]

Answer:

The mean and standard deviation for the z-scores in this distribution are 0 and 1 respectively.

Step-by-step explanation:

Let the random variable X follow a Normal distribution with mean μ and standard deviation σ.

The z-scores are standardized form of the raw scores X. It is computed by subtracting the mean (μ) from the raw score x and dividing the result by the standard deviation (σ).

$z=\frac{x-\mu}{\sigma}$

These z-scores also follow a normal distribution.

The mean is:

$E(z)=E[\frac{x-\mu}{\sigma} ]=\frac{1}{\sigma}\times [E(x)-\mu] =\frac{1}{\sigma}\times [\mu-\mu]=0$

The standard deviation is:

$Var(z)=Var[\frac{x-\mu}{\sigma} ]=\frac{1}{\sigma^{2}}\times [Var(x)-Var(\mu)] =\frac{\sigma^{2}-0}{\sigma^{2}}=1\\SD(z)=\sqrt{Var(z)}=1$

Thus, the mean and standard deviation for the z-scores in this distribution are 0 and 1 respectively.

8 0

3 years ago

Which function is graphed below?? TIMED HELP

nadezda [96]

That's the cosine x. The cosine of 0 is 1, so that's how you can tell. The sin of 0 is 0, so that's where the sin graph goes through the y axis

6 0

3 years ago

HELPPPP Which of the following is a solution of x2 + 5x = -2? (2 points)

harkovskaia [24]

Answer:

5.372 or −0.372

Step-by-step explanation:Changes made to your input should not affect the solution:

(1): "x2" was replaced by "x^2".

Step by step solution :

STEP

1

:

Trying to factor by splitting the middle term

1.1 Factoring x2-5x-2

The first term is, x2 its coefficient is 1 .

The middle term is, -5x its coefficient is -5 .

The last term, "the constant", is -2

Step-1 : Multiply the coefficient of the first term by the constant 1 • -2 = -2

Step-2 : Find two factors of -2 whose sum equals the coefficient of the middle term, which is -5 .

-2 + 1 = -1

-1 + 2 = 1

Observation : No two such factors can be found !!

Conclusion : Trinomial can not be factored

Equation at the end of step

1

:

x2 - 5x - 2 = 0

STEP

2

:

Parabola, Finding the Vertex

2.1 Find the Vertex of y = x2-5x-2

Parabolas have a highest or a lowest point called the Vertex . Our parabola opens up and accordingly has a lowest point (AKA absolute minimum) . We know this even before plotting "y" because the coefficient of the first term, 1 , is positive (greater than zero).

Each parabola has a vertical line of symmetry that passes through its vertex. Because of this symmetry, the line of symmetry would, for example, pass through the midpoint of the two x -intercepts (roots or solutions) of the parabola. That is, if the parabola has indeed two real solutions.

Parabolas can model many real life situations, such as the height above ground, of an object thrown upward, after some period of time. The vertex of the parabola can provide us with information, such as the maximum height that object, thrown upwards, can reach. For this reason we want to be able to find the coordinates of the vertex.

For any parabola,Ax2+Bx+C,the x -coordinate of the vertex is given by -B/(2A) . In our case the x coordinate is 2.5000

Plugging into the parabola formula 2.5000 for x we can calculate the y -coordinate :

y = 1.0 * 2.50 * 2.50 - 5.0 * 2.50 - 2.0

or y = -8.250

Parabola, Graphing Vertex and X-Intercepts :

Root plot for : y = x2-5x-2

Axis of Symmetry (dashed) {x}={ 2.50}

Vertex at {x,y} = { 2.50,-8.25}

x -Intercepts (Roots) :

Root 1 at {x,y} = {-0.37, 0.00}

Root 2 at {x,y} = { 5.37, 0.00}

Solve Quadratic Equation by Completing The Square

2.2 Solving x2-5x-2 = 0 by Completing The Square .

Add 2 to both side of the equation :

x2-5x = 2

Now the clever bit: Take the coefficient of x , which is 5 , divide by two, giving 5/2 , and finally square it giving 25/4

Add 25/4 to both sides of the equation :

On the right hand side we have :

2 + 25/4 or, (2/1)+(25/4)

The common denominator of the two fractions is 4 Adding (8/4)+(25/4) gives 33/4

So adding to both sides we finally get :

x2-5x+(25/4) = 33/4

Adding 25/4 has completed the left hand side into a perfect square :

x2-5x+(25/4) =

(x-(5/2)) • (x-(5/2)) =

(x-(5/2))2

Things which are equal to the same thing are also equal to one another. Since

x2-5x+(25/4) = 33/4 and

x2-5x+(25/4) = (x-(5/2))2

then, according to the law of transitivity,

(x-(5/2))2 = 33/4

We'll refer to this Equation as Eq. #2.2.1

The Square Root Principle says that When two things are equal, their square roots are equal.

Note that the square root of

(x-(5/2))2 is

(x-(5/2))2/2 =

(x-(5/2))1 =

x-(5/2)

Now, applying the Square Root Principle to Eq. #2.2.1 we get:

x-(5/2) = √ 33/4

Add 5/2 to both sides to obtain:

x = 5/2 + √ 33/4

Since a square root has two values, one positive and the other negative

x2 - 5x - 2 = 0

has two solutions:

x = 5/2 + √ 33/4

or

x = 5/2 - √ 33/4

Note that √ 33/4 can be written as

√ 33 / √ 4 which is √ 33 / 2

Solve Quadratic Equation using the Quadratic Formula

2.3 Solving x2-5x-2 = 0 by the Quadratic Formula .

According to the Quadratic Formula, x , the solution for Ax2+Bx+C = 0 , where A, B and C are numbers, often called coefficients, is given by :

- B ± √ B2-4AC

x = ————————

2A

In our case, A = 1

B = -5

C = -2

Accordingly, B2 - 4AC =

25 - (-8) =

33

Applying the quadratic formula :

5 ± √ 33

x = —————

2

√ 33 , rounded to 4 decimal digits, is 5.7446

So now we are looking at:

x = ( 5 ± 5.745 ) / 2

Two real solutions:

x =(5+√33)/2= 5.372

or:

x =(5-√33)/2=-0.372

6 0

3 years ago

Plot 2 points on y-4=-3/4(x+1)

MA_775_DIABLO [31]

x from -6 to 5, y from -10 to 10, y = -2x/3 -2).

4 0

3 years ago