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3 years ago

Find the solutions to the quadratic equation below by completing the square. x2 - 8x - 7 = 0

Mathematics

1 answer:

Furkat [3]3 years ago

3 0

Answer:

x=4- $\sqrt{23}$ , x=4+ $\sqrt{23}$

Step-by-step explanation:

(x^2-8x+16)-16-7=0

(x-4)^2=23

x=4- $\sqrt{23}$ , x=4+ $\sqrt{23}$

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Which table represents a linear function that has a slope of 5 and a y-intercept of 20?

AVprozaik [17]

Answer:

Step-by-step explanation:

Note that if it has a y- intercept of 20, this means that when x = 0 , y = 20

Find the table which shows that :)

3 0

3 years ago

Jules ran 2/3 miles. Miles ran 5/8 more than Jules. How many miles did Miles run?

kifflom [539]

2/3 is equivalent to 16/24
and 5/8 is equivalent to 15/24 miles
15/24+16/24= 31/24

31/24 simplifies to 1 6/24
Which simplifies down to 1 1/6

Miles ran 1 and 1/6 miles

3 0

3 years ago

Read 2 more answers

The Resource Conservation and Recovery Act mandates the tracking and disposal of hazardous waste produced at U.S. facilities. Pr

aniked [119]

Answer:

(a) $E(X) = 0.383$

The expected number in the sample that treats hazardous waste on-site is 0.383.

(b) $P(x = 4) = 0.000169$

There is a 0.000169 probability that 4 of the 10 selected facilities treat hazardous waste on-site.

Step-by-step explanation:

Professional Geographer (Feb. 2000) reported the hazardous waste generation and disposal characteristics of 209 facilities.

N = 209

Only eight of these facilities treated hazardous waste on-site.

r = 8

a. In a random sample of 10 of the 209 facilities, what is the expected number in the sample that treats hazardous waste on-site?

n = 10

The expected number in the sample that treats hazardous waste on-site is given by

$E(X) = \frac{n \times r}{N}$

$E(X) = \frac{10 \times 8}{209}$

$E(X) = \frac{80}{209}$

$E(X) = 0.383$

Therefore, the expected number in the sample that treats hazardous waste on-site is 0.383.

b. Find the probability that 4 of the 10 selected facilities treat hazardous waste on-site

The probability is given by

$P(x = 4) = \frac{\binom{r}{x} \binom{N - r}{n - x}}{\binom{N}{n}}$

For the given case, we have

N = 209

n = 10

r = 8

x = 4

$P(x = 4) = \frac{\binom{8}{4} \binom{209 - 8}{10 - 4}}{\binom{209}{10}}$

$P(x = 4) = \frac{\binom{8}{4} \binom{201}{6}}{\binom{209}{10}}$

$$ P(x = 4) = \frac{70 \times 84944276340}{35216131179263320}$

$P(x = 4) = 0.000169$

Therefore, there is a 0.000169 probability that 4 of the 10 selected facilities treat hazardous waste on-site.

8 0

3 years ago

Find an equation of the line that satisfies the given conditions. through (9, 7); perpendicular to the line y = 5

cluponka [151]

The answer would defintley be 69 if you want the right answer.

5 0

3 years ago

There are 5280 feet in a mile. What fraction is represented by 240 feet?

Sauron [17]

The fraction would be the portion over the total:

240 / 5280

Divide both top and bottom by 240 and the fraction simplifies to 1/22

The answer is 1/22

7 0

3 years ago