8x-2y+12x-2x-4y Show how to simplify the expression. Write the answer in factored form.

A sector of a circle makes a 127° angle at its centre. If the arc of the sector has length 36 mm, find

Veseljchak [2.6K]

Answer:

Approximately $68.5\; \rm mm$ .

Step-by-step explanation:

Convert the angle of this sector to radians:

$\begin{aligned}\theta &= 127^{\circ} \\ &= 127^{\circ} \times \frac{2\pi}{360^{\circ}} \\ &\approx 2.22\end{aligned}$ .

The formula $s = r\, \theta$ relates the arc length $s$ of a sector of angle $\theta$ (in radians) to the radius $r$ of this sector.

In this question, it is given that the arc length of this sector is $s = 36\; \rm mm$ . It was found that $\theta = 2.22$ radians. Rearrange the equation $s = r\, \theta$ to find the radius $r$ of this sector:

$\begin{aligned} r&= \frac{s}{\theta} \\ &\approx \frac{36\; \rm mm}{2.22} \\ &\approx 16.2\; \rm mm\end{aligned}$ .

The perimeter of this sector would be:

$\begin{aligned}& 2\, r + s \\ =\; & 2 \times 16.2\; {\rm mm} + 36\; {\rm mm} \\ =\; & 68.5\; \rm mm\end{aligned}$ .

8 0

3 years ago

A square desktop has an area of 324 square inches. What is the length of one side of the desktop

Sveta_85 [38]

Question: The area of a square is 324 square inches. What is the length of one side of the square?
The formula for finding area of squares is:

Length x Width

Squares have 4 sides, and all sides measure the same. If the area is 324 square units, that means the length and width are the same.

x X x=x2

X2=324

x squared(x²) is equal to 324. To find x, you have to do the opposite of squaring, which is finding the square root.

x2= 324 —> square root of 324=x

To find x, you have find the square root of 324.

Square root of 324 is 8

The length of one side is 18 inches
Check:
The formula for finding area is:

Length x Width

The length and width gotten was 18. Put that into the formula:

18 x 18

Multiply:

18 x 18= 324

That means the answer is correct. Your answer is 18 inches.
If you have any questions, feel free to ask in the comments! :)

8 0

3 years ago

The Information Technology Department at a large university wishes to estimate the proportion of students living in the dormitor

nadya68 [22]

Answer:

$n=\frac{0.5(1-0.5)}{(\frac{0.05}{1.96})^2}=384.16$

And rounded up we have that n=385

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

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".

Solution to the problem

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 99% of confidence, our significance level would be given by $\alpha=1-0.99=0.01$ and $\alpha/2 =0.005$ . And the critical value would be given by:

$z_{\alpha/2}=-2.58, z_{1-\alpha/2}=2.58$

The margin of error for the proportion interval is given by this formula:

$ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$ (a)

And on this case we have that $ME =\pm 0.05$ and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2}$ (b)

We can use as an estimator for p $\hat p =0.5$ . And replacing into equation (b) the values from part a we got:

$n=\frac{0.5(1-0.5)}{(\frac{0.05}{1.96})^2}=384.16$

And rounded up we have that n=385

3 0

3 years ago

Which is a reasonable unit to express a ropes length ? PLZ ANSWER FAST

Mrac [35]

Answer:

Depends on the type of rope but I would say feet

Step-by-step explanation:

7 0

3 years ago

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HELPPPPPPP ASAP!!!!

Sergeeva-Olga [200]

Answer: AB will be parallel to A'B'.

Step-by-step explanation: We know the definition of dilation about the centre. It is defined as the enlargement or shrinken of the original figure keeping the centre of dilation or the figure as fixed.

We are given ΔUVW and AB is perpendicular to UW. Now, if we dilate the triangle about the origin, then the triangle will either enlarge or shrink keeping the centre fixed.

Let us consider the enlarged triangle, ΔU'V'W' as shown in the attached figure. Also, line AB will move to the new position A'B'. We can clearly see that both the lines are parallel to each other.

Thus, the line segments AB and A'B' will be parallel too each other.

5 0

3 years ago

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