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3 years ago

How many roots do the following equations have? -12x2 - 25x + 5 + x3 = 0

Mathematics

1 answer:

adelina 88 [10]3 years ago

4 0

X= -1.970, 0.183, 13.786
Do you need an explanation?

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How does the value of the digit 2 in the number 32,000 compare with the value of the digit 2 in the number 26,000?

julsineya [31]

Answer:

the second value is ten times higher then the refference one

6 0

4 years ago

In a sample of 70 stores of a certain company, 62 violated a scanner accuracy standard. It has been demonstrated that the condi

uysha [10]

Answer:

We need at least 243 stores.

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the zscore that has a pvalue of $1 - \frac{\alpha}{2}$ .

The margin of error of the interval is:

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

For this problem, we have that:

$n = 70, p = \frac{62}{70} = 0.886$

95% confidence level

So $\alpha = 0.05$ , z is the value of Z that has a pvalue of $1 - \frac{0.05}{2} = 0.975$ , so $Z = 1.96$ .

Determine the number of stores that must be sampled in order to estimate the true proportion to within 0.04 with 95% confidence using the large-sample method.

We need at least n stores.

n is found when M = 0.04. So

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

$0.04 = 1.96\sqrt{\frac{0.886*0.114}}{n}}$

$0.04\sqrt{n} = 1.96\sqrt{0.886*0.114}$

$\sqrt{n} = \frac{1.96\sqrt{0.886*0.114}}{0.04}$

$(\sqrt{n})^{2} = (\frac{1.96\sqrt{0.886*0.114}}{0.04})^{2}$

$n = 242.5$

Rounding up

We need at least 243 stores.

5 0

3 years ago

What value of ‘W’ satisfies 8(w+4)=38+7w A. 8 B.6 C.11 D. 4.5

dlinn [17]

B. 6

Explanation: 8(6+4)= 80
38+ 7(6)= 80

5 0

3 years ago

Can someone help me with and and can you please write how you got it so I can understand

EastWind [94]

Answer:

12x + 4

Step-by-step explanation:

ok so a rectangle has 4 sides, 2 of which are called lengths, and 2 of which are widths.

length = 2x-3

width = 4x+5

the perimenter is the total of the 4 sides.

2(2x-3) = 4x-6 (the total for lengths)

2(4x+5) = 8x+10 (the total for widths)

add the 2 together:

12x+4

8 0

3 years ago

Read 2 more answers

The amount Lin's sister earns at her part-time job is proportional to the number

jarptica [38.1K]

the equation framed in the form of y=kx is $y = 9.6(x)$ and , x as a function of y $x=\frac{1}{ 9.6}(y)$ .

Step-by-step explanation:

Here we have , The amount Lin's sister earns at her part-time job is proportional to the number of hours she works. She earns $9.60 per hour. We need to find an equation in the form y=kx to describe this situation, where x represents the hours she works and y represents the dollars she earns.Is y a function of x . Also , Write an equation describing x as a function of y . Let's find out:

Here , Lin's sister earns $9.60 per hour . Let x represents the hours she works and y represents the dollars she earns . So , According to question following is the equation framed in the form of y=kx :

⇒ $y = 9.6(x)$

Yes, y is a function of x , as a straight line with a slope of 9.6

Now , x as a function of y :

⇒ $\frac{y}{ 9.6}=(x)$

⇒ $x=\frac{1}{ 9.6}(y)$

Therefore , the equation framed in the form of y=kx is $y = 9.6(x)$ and , x as a function of y $x=\frac{1}{ 9.6}(y)$ .

3 0

4 years ago