I really need help please. I do not understand this math question;?

Triss [41]

Equation: 5x² - 3x - 14

= 5x² - 10x + 7x - 14

= 5x(x - 2) 7(x - 2)

= (5x + 7)(x - 2)

In short, Your Answer would be: Option B

Hope this helps!

6 0

2 years ago

Read 2 more answers

Drew has two cats. One cat weighs 17 pounds, and the other one weighs 12 1/2 pounds. Audrey’s dog weighs 33 pounds. What is the

Step2247 [10]

Answer: 3.5 pounds

Step-by-step explanation:

17+12.5=29.5

33-29.5=3.5

4 0

3 years ago

Solve the following quadratic equations by completing the square.<br><br> y^2-14y+48=0

NISA [10]

Answer:

y = 6 or 8

Step-by-step explanation:

1. Subtract the constant:

y^2 -14y = -48

2. Add the square of half the y-coefficient:

y^2 -14y +49 = -48 +49

Write as a square, if you like:

(y -7)^2 = 1

3. Take the square root:

y -7 = ±√1 = ±1

4. Add the opposite of the constant on the left:

y = 7 ±1 = 6 or 8

The solution is y = 6 or y = 8.

5 0

3 years ago

Life Expectancies In a study of the life expectancy of people in a certain geographic region, the mean age at death was years an

Sphinxa [80]

Answer:

The probability that the mean life expectancy of the sample is less than X years is the p-value of $Z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$ , in which $\mu$ is the mean life expectancy, $\sigma$ is the standard deviation and n is the size of the sample.

Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the z-score of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean $\mu$ and standard deviation $\sigma$ , the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean $\mu$ and standard deviation $s = \frac{\sigma}{\sqrt{n}}$ .

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

We have:

Mean $\mu$ , standard deviation $\sigma$ .

Sample of size n:

This means that the z-score is now, by the Central Limit Theorem:

$Z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$

Find the probability that the mean life expectancy will be less than years.

The probability that the mean life expectancy of the sample is less than X years is the p-value of $Z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$ , in which $\mu$ is the mean life expectancy, $\sigma$ is the standard deviation and n is the size of the sample.

8 0

2 years ago

Marcus earns $8.40 per hour. He works for 26 hours each week, 48 weeks each year. If he earns over $10,000, then Marcus has to p

MAVERICK [17]

We have been given that Marcus works for 26 hours each week and 48 weeks each year.

Thus in a year he works for $26 \times 48 = 1248$ hours.