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3 years ago

How do you solve linear equations (short definition)

Mathematics

1 answer:

Ede4ka [16]3 years ago

6 0

Answer:

by moving x's onto one side and the constants to the other

Step-by-step explanation:

hope that helps

You might be interested in

Suppose that a standardized biology exam has a mean score of 80% correct, with a standard deviation of 3. The school administrat

NemiM [27]

Answer:

The 99% confidence interval is between 62.36%(lower bound) and 89.64%(upper bound).

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 $1 - \frac{\alpha}{2}$ .

A sample of 65 students from the freshmen class is used and a mean score of 76% correct is obtained.

This means that $n = 65, \pi = 0.76$

99% confidence level

So $\alpha = 0.005$ , z is the value of Z that has a pvalue of $1 - \frac{0.005}{2} = 0.995$ , so $Z = 2.575$ .

The lower limit of this interval is:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.76 - 2.575\sqrt{\frac{0.76*0.24}{65}} = 0.6236$

The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.76 + 2.575\sqrt{\frac{0.76*0.24}{65}} = 0.8964$

0.6236*100 = 62.36%

0.8964*100 = 89.64%

The 99% confidence interval is between 62.36%(lower bound) and 89.64%(upper bound).

6 0

3 years ago

Simplify the following expression below:

IrinaK [193]

So, 4/3 - 2i

4/3 - 2i = 12/13 + i8/13

multiply by the conjugate:
3 + 2i/3 + 2i
= 4(3 + 2i)/(3 - 2i) (3 + 2i)
(3 - 2i) (3 + 2i) = 13

(3 - 2i) (3 + 2i)

apply complex arithmetic rule: (a + bi) (a - bi) = a^2 + b^2
a = 3, b = - 2
= 3^2 + (- 2)^2

refine: = 13
= 4(3 + 2i)/13

distribute parentheses:
a(b + c) = ab + ac
a = 4, b = 3, c = 2i
= 4(3) + 4(2i)

Simplify:
4(3) + 4(2i)
12 + 8i

4(3) + 4(2i)
Multiply the numbers: 4(3) = 12
= 12 + 2(4i)

Multiply the numbers: 4(2) = 8
= 12 + 8i

12 + 8i
= 12 + 8i/13

Group the real par, and the imaginary part of the complex numbers:

Your answer is: 12/13 + 8i/13

Hope that helps!!!

7 0

3 years ago

What is 4r + 3r + 7y + 5r - 2y - 6r ? A. 5r + 5y B. 29r - 27y C. 27ry

Sonja [21]

Step-by-step explanation:

It's 6r+5y. But it's not in the option

3 0

3 years ago

A group of researchers wants to know whether men are more likely than women to contract a novel coronavirus. They surveyed two r

olasank [31]

Answer:

Test statistic Z= 0.13008 < 1.96 at 0.10 level of significance

null hypothesis is accepted

There is no difference proportion of positive tests among men is different from the proportion of positive tests among women

Step-by-step explanation:

Step(I):-

Given surveyed two random samples of 390 men and 360 women who were tested

first sample proportion

$p_{1} = \frac{360}{390} = 0.9230$

second sample proportion

$p_{2} = \frac{47}{52} = 0.9038$

Step(ii):-

Null hypothesis : H₀ : There is no difference proportion of positive tests among men is different from the proportion of positive tests among women

Alternative Hypothesis:-

There is difference between proportion of positive tests among men is different from the proportion of positive tests among women

$Z = \frac{p_{1}- p_{2} }{\sqrt{PQ(\frac{1}{n_{1} }+\frac{1}{n_{2} } } }$

where

$P = \frac{n_{1}p_{1} +n_{2} p_{2} }{n_{1}+n_{2} }$

P = 0.920

$Z= \frac{0.9230-0.9038}{\sqrt{0.920 X0.08(\frac{1}{390}+\frac{1}{52} } )}$

Test statistic Z = 0.13008

Level of significance = 0.10

The critical value Z₀.₁₀ = 1.645

Test statistic Z=0.13008 < 1.645 at 0.1 level of significance

Null hypothesis is accepted

There is no difference proportion of positive tests among men is different from the proportion of positive tests among women

7 0

3 years ago

150 calories and 30 grams how many calories are in 7 grams

exis [7]

Answer:

35 calories

Step-by-step explanation:

create a proportion and solve.

30/150= 7/x

7 0

3 years ago