4. Find the solution of y = 2x + 5 for x = 1.<br> A (1, 7)<br> B (3, 1)<br> C (1, 12)<br> D (1, -2)

Alexxx [7]

The answer is negative 2x squared minus 3x

6 0

2 years ago

Rachael got a 550 on the analytical portion of the Graduate Record Exam (GRE). If GRE scores are normally distributed and have m

valina [46]

Answer:

Z=-2

This value means that the score of Rachel 550 it's 2 deviations below the mean of the population $\mu=600$

Step-by-step explanation:

1) Previous concepts

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".

$\mu=600$ represent the population mean for the Graduate Record Exam (GRE)

$\sigma=25$ represent the population standard deviation for Graduate Record Exam (GRE)

2) Solution to the problem

Let X the random variable that represent the Graduate Record Exam (GRE) of a population, and for this case we know the distribution for X is given by:

$X \sim N(600,25)$

Where $\mu=600$ and $\sigma=25$

We want to find the z score for a score of 550. And in order to do this we need to apply the formula for the z score given by:

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

If we apply this formula to our probability we got this:

$z=\frac{550-600}{25}=-2$

So the answer for our case would be Z=-2

This value means that the score of Rachel 550 it's 2 deviations below the mean of the population $\mu=600$

7 0

2 years ago

What is the answer to 3 1/2 - 2 1/8

DerKrebs [107]

Answer:

$Exact form:\\\frac{11}{8} \\Decimal form:\\1.375\\Mixed number form:\\1\frac{3}{8}$

Step-by-step explanation:

hope this helps

4 0

3 years ago

Read 2 more answers

9234 divided by 52 but what is the remainder

HACTEHA [7]

Answer:

In a decimal it would be 177.577

In a fraction it would be 177 577/1000

5 0

2 years ago

Read 2 more answers

Prove the identity.

Delvig [45]

Answer:

D. Pythagorean

Step-by-step explanation:

Given the identity

cos²x - sin²x = 2 cos²x - 1.

To show that the identity is true, we need to show that the left hand side is equal to right hand side or vice versa.

Starting from the left hand side

cos²x - sin²x ... 1

According to Pythagoras theorem, we know that x²+y² = r² in a right angled triangle. Coverting this to polar form, we have:

x = rcostheta

y = rsintheta

Substituting into the Pythagoras firnuka we have

(rcostheta)²+(rsintheta)² = r²

r²cos²theta+r²sin²theta = r²

r²(cos²theta+sin²theta) = r²

(cos²theta+sin²theta) = 1

sin²theta = 1 - cos²theta

sin²x = 1-cos²x ... 2

Substituting equation 2 into 1 we have;

= cos²x-(1-cos²x)

= cos²x-1+cos²x

= 2cos²x-1 (RHS)

This shows that cos²x -sin²x = 2cos²x-1 with the aid of PYTHAGORAS THEOREM

5 0

3 years ago

4. Find the solution of y = 2x + 5 for x = 1. A (1, 7) B (3, 1) C (1, 12) D (1, -2)