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3 years ago

What is the value of 12(3x+5x) when x=7

Mathematics

2 answers:

Nadusha1986 [10]3 years ago

6 0

1,128. I'm glad you asked for my help!!!!!!!!

Anna35 [415]3 years ago

5 0

Subsitute 7 for x

12(3(7)+5(7))
12(21+35)
12(56)
672

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What is the equation of the line that is parallel to the

amm1812

Answer:

-6

Step-by-step explanation:

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3 years ago

A sample of 16 small bags of the same brand of candies was selected. Assume that the population distribution of bag weights is n

Olegator [25]

Answer:

i) $2 - 1.64 \frac{0.1}{\sqrt{16}}= 1.959$

$2 + 1.64 \frac{0.1}{\sqrt{16}}= 2.041$

So then the 90% confidence interval is given by (1.959, 2.041)

ii) Figure attached

iii) $ME= 1.64 *\frac{0.1}{\sqrt{16}}= 0.041$

Step-by-step explanation:

Previous concepts

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The confidence interval is given by this formula:

$\bar X \pm z_{\alpha/2} \frac{\sigma}{\sqrt{n}}}$ (1)

And for a 90% of confidence the significance is given by $\alpha=1-0.9=0.1$ , and $\frac{\alpha}{2}=0.05$ . Since we know the population standard deviation we can calculate the critical value $z_{0.05}= \pm 1.64$

We know the folllowing data:

$\bar X = 2$ represent the sample mean

$\sigma = 0.1$ represent the population deviation

n =16 represent the sample size

Part i)

If we replace the values given into formula (1) we got:

$2 - 1.64 \frac{0.1}{\sqrt{16}}= 1.959$

$2 + 1.64 \frac{0.1}{\sqrt{16}}= 2.041$

So then the 90% confidence interval is given by (1.959, 2.041)

Part ii)

Figure attached. We have the illustration for the confidence interval obtained.

Part iii)

The margin of error is given by:

$ME=z_{\alpha/2} \frac{\sigma}{\sqrt{n}}}$

And if we replace we got:

$ME= 1.64 *\frac{0.1}{\sqrt{16}}= 0.041$

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3 years ago

If a triangle has a base of 5 cm and a height of 6 cm what’s it’s area?

Margarita [4]

Answer:

the area is 30 you have to muiltly the two together

Step-by-step explanation:

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3 years ago

Which description of the vector shown is correct ?

BartSMP [9]

Answer:

(B) The magnitude is 7sqrt2, and the direction angle is approximately 135 degrees.

Step-by-step explanation:

From the figure, the coordinate of the tail of the vector,

$(x_1,y_1)=(3,-6).$

The coordinate of the head of the vector,

$(x_2,y_2)=(-4,1).$

The magnitude of a vector is the length between the head and tail of the vector.

By using the distance formula,

the magnitude of the vector $= \sqrt{(1-(-6))^2+(-4-3)^2}$

$=\sqrt{(7^2+(-7)^2}\\\\=\sqrt{98}\\\\=7\sqrt{2}$

Now, let $\theta$ be the angle made by the vector with the positive direction of the x-axis, so

$\tan\theta = \frac{y_2-y_1}{x_2-x_1}\\\\\Rightarrow \tan\theta = \frac{1-(-6)}{-4-3}=\frac{7}{-7}=-1 \\\\\Rightarrow \theta = \tan^{-1}(-1) \\\\\Rightarrow \theta =\pi- \tan^{-1}1 \\\\\Rightarrow \theta = \pi-\frac{\pi}{4} \\\\\Rightarrow \theta =\frac{3\pi}{4} \\\\\Rightarrow \theta = 135 ^{\circ}.$