What is the solution to –2(8x

HELP PLEASE

tiny-mole [99]

Answer:

The answer would be B.) 5x - 3y = 30

8 0

3 years ago

What is the solution to the system of equations?

Dovator [93]

Answer:

Step-by-step explanation:

$\left\{\begin{array}{ccc}x+3y+2z=8&(1)\\3x+y+3z=-10&(2)\\-2x-2y-z=10&(3)\end{array}\right\qquad\text{subtract both sides of the equations (1) from (2)}\\\\\underline{-\left\{\begin{array}{ccc}3x+y+3z=-10\\x+3y+2z=8\end{array}\right }\\.\qquad2x-2y+z=-18\qquad(4)\qquad\text{add both sides of the equations (3) and (4)}\\\\\underline{+\left\{\begin{array}{ccc}-2x-2y-z=10\\2x-2y+z=-18\end{array}\right}\\.\qquad-4y=-8\qquad\text{divide both sides by (-4)}\\.\qquad\qquad y=2\qquad\text{put the value of y to (1) and (3)}$

$\left\{\begin{array}{ccc}x+3(2)+2z=8\\-2x-2(2)-z=10\end{array}\right\\\left\{\begin{array}{ccc}x+6+2z=8&\text{subtract 6 from both sides}\\-2x-4-z=10&\text{add 4 to both sides}\end{array}\right\\\left\{\begin{array}{ccc}x+2z=2&\text{multiply both sides by 2}\\-2x-z=14\end{array}\right\\\underline{+\left\{\begin{array}{ccc}2x+4z=4\\-2x-z=14\end{array}\right}\qquad\text{add both sides of the equations}\\.\qquad\qquad3z=18\qquad\text{divide both sides by 3}\\.\qquad\qquad z=6\qquad\text{put the value of z to the first equation}$

$x+2(6)=2\\x+12=2\qquad\text{subtract 10 from both sides}\\x=-10$

4 0

3 years ago

( m + 4 ) ( m + 1 )

love history [14]

(m+4)(m+1)

=m^2+5m+4........

3 0

3 years ago

The average amount of time to finish this quiz is 26 minutes with a standard deviation of 1.2 minutes. What is the probability t

boyakko [2]

Answer:

What is the probability that you will finish this quiz in 23.84 minutes or less?

0.03593

Write your answer as a percentage with 2 decimals

= 3.59%

Step-by-step explanation:

The z score formula is given as:

z = (x-μ)/σ, where x is the raw score, μ is the population mean, and σ is the population standard deviation.

Mean = 26 minutes

Standard deviation = 1.2 minutes.

The probability that you will finish this quiz in 23.84 minutes or less(≤) is calculated as:

z = (x-μ)/σ

z = 23.84 - 26/1.2

z = -1.8

Probability value from Z-Table:

P(x ≤ 23.84) = 0.03593

Converting to percentage

0.03593 × 100

= 3.593

Approximately to 2 decimal places = 3.59%

7 0

3 years ago

A 9-year-old girl did a science fair experiment in which she tested professional touch therapists to see if they could sense he

Orlov [11]

Answer:

We conclude that the the touch therapists does not use a method equivalent to random guesses.

Yes, the results suggest that touch therapists are effective.

Step-by-step explanation:

We are given that in a 9-year-old girl did a science fair experiment in which she tested professional touch therapists to see if they could sense her energy field.

Among 264264 trials, the touch therapists were correct 105105 times.

Let p = proportion that touch therapists uses a random guess method.

Here, random guess means; p = 50%

So, Null Hypothesis, $H_0$ : p = 50% {means that the touch therapists use a method equivalent to random guesses}

Alternate Hypothesis, $H_A$ : p $\neq$ 50% {means that the touch therapists does not use a method equivalent to random guesses}

The test statistics that would be used here One-sample z proportion statistics;

T.S. = $\frac{\hat p-p}{\sqrt{\frac{\hat p(1-\hat p)}{n} } }$ ~ N(0,1)

where, $\hat p$ = sample proportion of touch therapists were correct = $\frac{105}{264}$ = 0.39

n = sample of trials = 264

So, test statistics = $\frac{\frac{105}{264} -0.50}{\sqrt{\frac{\frac{105}{264}(1-\frac{105}{264})}{264} } }$

= -3.395

The value of z test statistics is -3.395.

Now, at 0.05 significance level the z table gives critical value of -1.96 and 1.96 for two-tailed test. Since our test statistics does not lie within the range of critical values of z, so we have sufficient evidence to reject our null hypothesis as it will in the rejection region due to which we reject our null hypothesis.

Therefore, we conclude that the the touch therapists does not use a method equivalent to random guesses.

Yes, the results suggest that touch therapists are effective.

3 0

3 years ago

What is the solution to –2(8x – 4) < 2x + 5?