Solve the system by elimination -6x + 6y = 0 9x

Need help resolving the following quadratic expressions:

Sedaia [141]

Answer:

first answer for (a) is -15=0

second answer for (b) is =9y+3

Step-by-step explanation:

its juss so easy

8 0

3 years ago

Compute: (4+9) - 3(6)/2 + 8 4 O 11.2

Andre45 [30]

Answer:

the answer is 12

Step 1. Perform the operations inside the parenthesis:

(4 + 9) − 3(6) ÷ 2 + 8 = 13 - 18 ÷ 2 + 8

Step 2. Division has advantage over subtraction and addition:

13 - 18 ÷ 2 + 8 = 13 - 9 + 8

Step 3. Subtract and add:

13 - 9 + 8 = 12

Step-by-step explanation:

6 0

4 years ago

Read 2 more answers

At the Oral Language Fair, Tom’s speech took 9 1/2 minutes. Andrea’s speech was 7/8 as long as Tom’s. How long was Andrea’s spee

Grace [21]

7/8 * 9 1/2 =. 8.31 minutes

5 0

3 years ago

Added to Six Flags St. Louis in the Colossus is a giant Ferris wheel. Its diameter is 165 feet, it rotates at a rate of about 1.

vlada-n [284]

Answer:

The height of the rider as a function of time is $h(t) = 15 + 82.5\cdot (1-\cos 0.168t) \,[ft]$ , where time is measured in seconds.

Step-by-step explanation:

Given that Ferris wheel rotates at constant rate and rider begins at the bottom of the wheel, the height of the rider as a function of time is modelled after this expression:

$h(t) = h_{bottom} + (1-\cos \omega t)\cdot r_{w}$

Where:

$h_{bottom}$ - Height of the bottom with respect to ground, measured in feet.

$\omega$ - Angular speed of the ferris wheel, measured in radians per second.

$t$ - Time, measured in seconds.

$r_{w}$ - Radius of the Ferris wheel, measured in feet.

The angular speed of the ferris wheel, measured in radians per second, is obtained from the following expression:

$\omega = \frac{\pi}{30}\cdot \dot n$

Where:

$\dot n$ - Angular speed of the ferris wheel, measured in revolutions per minute.

If $\dot n = 1.6\,rpm$ , then:

$\omega = \frac{\pi}{30}\cdot (1.6\,rpm)$

$\omega \approx 0.168\,\frac{rad}{s}$

Now, given that $h_{bottom} = 15\,ft$ , $r_{w} = 82.5\,ft$ and $\omega \approx 0.168\,\frac{rad}{s}$ , the height of the rider as a function of time is:

$h(t) = 15 + 82.5\cdot (1-\cos 0.168t) \,[ft]$

4 0

3 years ago

The following questions pertain to the properties of the STANDARD NORMAL distribution. (a) True or False: The distribution is be

SashulF [63]

Answer:

a. The distribution is bell-shaped and symmetric: True.

b. The distribution is bell-shaped and symmetric: True.

c. The probability to the left of the mean is 0: False.

d. The standard deviation of the distribution is 1: True.

Step-by-step explanation:

The Standard Normal distribution is a normal distribution with mean, $\\ \mu = 0$ , and standard deviation, $\\ \sigma = 1$ .

It is important to recall that the parameters of the Normal distributions, namely, $\\ \mu$ and $\\ \sigma$ characterized them.

We can use the Standard Normal distribution to find probabilities for any normally distributed data. All we have to do is normalized them through z-scores:

$\\ z = \frac{x - \mu}{\sigma}$ [1]

Where $\\ x$ is the raw score that we want to standardize.

Therefore, taking into account all this information, we can answer the following questions about the Standard Normal distribution:

(a) True or False: The distribution is bell-shaped and symmetric

Answer: True. As the normal distribution, the standard normal distribution is also bell-shape and it is symmetrical around the mean. The standardized values or z-scores, which represent the distance from the mean in standard deviations units, are the same but when it is above the mean, the z-score is positive, and negative when it is below the mean. This result is a consequence of the symmetry of this distribution respect to the mean of the distribution.

(b) True or False: The mean of the distribution is 0.

Answer: True. Since the Standard Normal uses standardized values, if we use [1], we have:

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

If $\\ x = \mu$

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

$\\ z = \frac{0}{\sigma}$

$\\ z = 0$

Then, the value for the mean is where z = 0. A z-score is a linear transformation of the original data. For this reason, the transformed mean is equivalent to 0 in the standard normal distribution. We only need to find distances from this zero in standard normal deviations or z-scores to find probabilities.

(c) True or False: The probability to the left of the mean is 0.

Answer: False. The probability to the left of the mean is not 0. The cumulative probability from $\\ -\infty$ until the mean is 0.5000 or $\\ P(-\infty < z < 0) = 0.5$ .

(d) True or False: The standard deviation of the distribution is 1.

Answer: True. The standard normal distribution is a convenient way of calculate probabilities for any normal distribution. The standardized variable, represented by [1], permits us to use one table (the standard normal table) for all normal distributions.

In this distribution, the z-score is always divided by the standard deviation of the population. Then, the standard deviation for the standard normal distribution are times or fractions of the standard deviation of the population, since we divide the distance of a raw score from the mean of the population, $\\ x - \mu$ , by it. As a result, the standard deviation for the standard normal distribution will be times (1, 2, 3, 0.96, -1, -2, etc) the standard deviation of any normal distribution, $\\ \sigma$ .

In this case, the linear transformation of the original data for one standard deviation from the mean is z = 1. Therefore, the standard deviation for the standard normal distribution is the unit.

6 0

3 years ago

Read 2 more answers

Solve the system by elimination -6x + 6y = 0 9x - 8y = 4