All categories

3 years ago

2. If f(x) = x - 7 and g(x) = 2x + 5, then what is f(x) * g(x)?

Mathematics

1 answer:

AysviL [449]3 years ago

7 0

Answer:

2x² - 9x - 35

Step-by-step explanation:

f(x) × g(x) = (x - 7)(2x + 5)

Each term in the second factor is multiplied by each term in the first factor, that is

x(2x + 5) - 7(2x + 5) ← distribute both parenthesis

= 2x² + 5x - 14x - 35 ← collect like terms

= 2x² - 9x - 35

You might be interested in

The volume of a cylinder is 770 cm. It's height is 5 cm. Find its approximate radius.

Alinara [238K]

Hey there,

The equation for the volume of a cylinder is V = πr²h.

The first step into finding the radius is to plug in what you already know into the equation:

770 = πr²5

We divide both sides by 5:

154 = πr²

Now we divide both sides by π:

49.0197224723 = r²

Finally we just do the square root of 49.0197224723:

7.0014086063 = r

The radius therefore would be about 7cm.

Hope I helped,

Amna

3 0

3 years ago

Wilma can mow a lawn in 80 mintues.Melissa can mow the same lawn in 120 minutes. How long does it take for both Wilma and Meliss

Luba_88 [7]

There is a formula for that;
Total time = (Worker 1 * Worker 2) / (Worker 1 + Worker 2)
Total time = (80 * 120) / (80 + 120)
Total time = 9,600 / 200
Total time = 48 minutes

4 0

3 years ago

An amount of #550,000.00 was realised when a principal,x was saved 2% simple interest for 5 years. Find the value of x

Zarrin [17]

Answer:

x = 250,000

Step-by-step explanation:

A = P(1 + rt)

550,000 = x (1 +2% x 60)

550,000/(1 +2% x 60) = 250,000

x = 250,000

<u>Check your answer</u>

A = 250,000 (1+2%x60)

A = 550,000

pls mark brainliest

5 0

3 years ago

Ricardo and Tammy practice putting golf balls. Ricardo makes 47% of his putts and Tammy makes 51% of her putts. Suppose that Ric

yaroslaw [1]

Answer:

0.3821 = 38.21% probability that Ricardo makes a higher proportion of putts than Tammy.

Step-by-step explanation:

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

Normal probability distribution

When the distribution is normal, we use the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore 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 pvalue, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem estabilishes 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.

For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean $\mu = p$ and standard deviation $s = \sqrt{\frac{p(1-p)}{n}}$

Subtraction of normal variables:

When we subtract normal variables, the mean of the subtraction will be the subtraction of the means, while the standard deviation will be the square root of the sum of the variances.

Ricardo makes 47% of his putts, and attempts 25 putts.

By the Central Limit Theorem, we have that:

$\mu_R = 0.47, s_R = \sqrt{\frac{0.47*0.53}{25}} = 0.0998$