The solutions to the given system of equations are x = 4 and y = -9
<h3>Simultaneous linear equations</h3>
From the question, we are to determine the solutions to the given system of equations
The given system of equations are
-8x-4y=4 --------- (1)
-5x-y=-11 --------- (2)
Multiply equation (2) by 4
4 ×[-5x-y=-11 ]
-20x -4y = -44 -------- (3)
Now, subtract equation (3) from equation (1)
-8x -4y = 4 --------- (1)
-(-20x -4y = -44) -------- (3)
12x = 48
x = 48/12
x = 4
Substitute the value of x into equation (2)
-5x -y = -11
-5(4) -y = -11
-20 -y = -11
-y = -11 + 20
-y = 9
∴ y = -9
Hence, the solutions to the given system of equations are x = 4 and y = -9
Learn more on Simultaneous linear equations here: brainly.com/question/26310043
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Answer:
We are 95% confident that the true proportion of TV audience is between 65.15% and 65.85%
Step-by-step explanation:
-From the given information, 
.
-We calculate the confidence interval using this value at 95% confidence level:
![CI=\hat p\pm z \sqrt{\frac{\hat p(1-\hat p)}{n}}\\\\\\=0.65\pm 1.96\times \sqrt{\frac{0.65\times 0.35}{12000}}\\\\\\=0.65\pm 0.0085\\\\\\=[0.6415,0.6585]](https://tex.z-dn.net/?f=CI%3D%5Chat%20p%5Cpm%20z%20%5Csqrt%7B%5Cfrac%7B%5Chat%20p%281-%5Chat%20p%29%7D%7Bn%7D%7D%5C%5C%5C%5C%5C%5C%3D0.65%5Cpm%201.96%5Ctimes%20%5Csqrt%7B%5Cfrac%7B0.65%5Ctimes%200.35%7D%7B12000%7D%7D%5C%5C%5C%5C%5C%5C%3D0.65%5Cpm%200.0085%5C%5C%5C%5C%5C%5C%3D%5B0.6415%2C0.6585%5D)
So, the 95% confidence interval is (0.6515,0.6585).
Hence, we are 95% confident that the true proportion of TV audience is between 65.15% and 65.85%.
Answer:
option B
Step-by-step explanation:
Given in the question a complex fraction
<h3>Step1</h3>
To divide complex numbers, you must multiply by the conjugate. To find the conjugate of a complex number all you have to do is change the sign between the two terms in the denominator.
<h3>Step2</h3>
Distribute (or FOIL) in both the numerator and denominator to remove the parenthesis.
<h3>Step3</h3>
Simplify the powers of i, specifically remember that i² = –1.
<h3>Step4</h3>
<h3>Step5</h3>
simply
Answer:
c. 120 units^3
Step-by-step explanation:
L x W x H = <em>V</em>
3 x 4 / 2 = 6
6 x 20 = 120
Since in this case we are
only using the variance of the sample and not the variance of the real population,
therefore we use the t statistic. The formula for the confidence interval is:
<span>CI = X ± t * s / sqrt(n) ---> 1</span>
Where,
X = the sample mean = 84
t = the t score which is
obtained in the standard distribution tables at 95% confidence level
s = sample variance = 12.25
n = number of samples = 49
From the table at 95%
confidence interval and degrees of freedom of 48 (DOF = n -1), the value of t
is around:
t = 1.68
Therefore substituting the
given values to equation 1:
CI = 84 ± 1.68 * 12.25 /
sqrt(49)
CI = 84 ± 2.94
CI = 81.06, 86.94
<span>Therefore at 95% confidence
level, the scores is from 81 to 87.</span>
