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Kisachek [45]
3 years ago
6

Find the discriminant and the number of real roots for this equation 2 + 2x+7= 0

Mathematics
1 answer:
miv72 [106K]3 years ago
4 0

Step-by-step explanation:

2+2x+7=0

collecting like terms

2x+9=0

2x=-9

divide both sides by 2

x=-4.5

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A rectangular aquarium 3 ft. x 2 ft. 1 ft. is 2/3 full of water. In cubic feet, how much water is in the tank
tatuchka [14]

To find the volume of a rectangular prism, we must multiply the length * width * height.


In this case,


Volume = 3 ft * 2 ft * 1 ft

= 6 ft^3


Because this tank is 2/3 full with water, to find out how much water is in the tank, we must multiply 2/3 by the total volume of the tank (6 ft^3).


2/3 * 6 ft^3 = 4 ft^3


This means that there are 4 cubic feet of water in the tank.


Hope this helps!

6 0
3 years ago
Researchers fed mice a specific amount of Toxaphene, a poisonous pesticide, and studied their nervous systems to find out why To
Mkey [24]

Answer:

a. The mean refractory period= 1.85 and the standard error = 0.06455

b.  90% confidence interval for the mean absolute refractory period for all mice when subjected to the same treatment = 1.6981, 2.0019

c. Yes, the data give good evidence to support this theory

Step-by-step explanation:

a.  The table below shows the calculations:

                 X                (X-mean)^2

                1.7             0.0225

                1.8                 0.0025

                1.9                 0.0025

                2.0                 0.0225

Total        7.4                  0.05

Sample size: n=4

The mean is:  \bar{x} = \frac{7.4}{4} = 1.85

The sample standard deviation, s = \sqrt{\frac{\sum \left ( x-\bar{x} \right )^{2}}{n-1}}=0.1291

The standard error, se= \frac{s}{\sqrt{n}}=\frac{0.1291}{2} = 0.06455

b. Degree of freedom: df = n-1 = 3

Critical value of t for 90% confidence interval is: 2.3534

The confidence interval is  \bar{x}\pm t_{c}se = 1.85\pm 2.3534\cdot 0.06455=1.85\pm 0.1519 = (1.6981, 2.0019)

c. The Hypotheses are:

H_{0}:\mu=1.3,H_{1}:\mu>1.3

So the test statistics will be

t=\frac{\bar{x}-\mu}{s/\sqrt{n}}=8.52

The p-value is: 0.0017

We reject the null hypothesis because p-value is less than 0.05 . This indicates that the data gave good evidence to support this theory.

4 0
3 years ago
-10x + 35 + 5x = -5x + 20 PLs fix this error and answer it can you also show me the steps so I understand?
Vedmedyk [2.9K]

Answer:

-10x + 35 + 5x simplifies to -5x + 35.

Step-by-step explanation:

Combine Like Terms:

= −10x + 35 + 5x

= (−10x + 5x) + (35)

= −5x + 35

Hope this helps!

6 0
3 years ago
Read 2 more answers
Credit card companies lose money on cardholders who fail to pay their minimum payments. They use a variety of methods to encoura
Ivahew [28]

Answer with  explanation:

A x% confidence interval interprets that a person can be x% confident thatthe true mean lies in it.

Here, Credit card companies is using the collection agency to justify the cost of , the agency must collect an average of at least $200 per customer.

i.e. H_0:\mu \geq200,\ \ \ H_a:\mu

The 90% confidence interval on the mean collected amount was reported as ($190.25, $250.75) .

I recommend that we can be 90% sure that the true mean collected amount  lies in ($190.25, $250.75).

Also, $200 lies in it such that it is more far from $250.75 than $190.25, that means there are large chances of having an average is at least $200 per customer.

8 0
3 years ago
If Charlie liked dogs, and Macy's hat was green, how fast was the car, that the dog's dad was driving?
Likurg_2 [28]

Answer: The car wasn't going fast at all because dogs can't drive

Step-by-step explanation:

4 0
3 years ago
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