The steps for determining the center and radius of a circle using the completing the square method are shown below:

1 answer:

7 0

The answer is option c.
That is, the wrong step in step 6. It was written that the center of the circunference is the point (2.1). However, the general equation of a circumference is:
(X- (a)) ^ 2 + (Y- (b)) ^ 2 = r ^ 2
Where the point (a, b) is the center of the circle.
So for this case the point for the center is: (-2, -1)

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A top-loading washing machine has a cylindrical basket that rotates about a vertical axis. The basket of one such machine starts

damaskus [11]

Answer:

$n_{tot}=44rev$

Step-by-step explanation:

In order to solve this problem we can make use of the following formula:

$\theta=(\frac{\omega_{f}+\omega_{0}}{2})t$

where θ is the total angle the basket has turned, ω is the angular velocity and t is the time.

Generally theta is written in radians and omega is written in radians per second. Now, since the revolutions are directly related to the radians and they want us to write our answer in revolutions, we can directly use the provided speeds in the formula, so we can rewrite it as:

$n=(\frac{f_{f}+f_{0}}{2})t$

where n represents the number of revolutions and f is the frequency at which the basket is turning.

The movement of the cylindrial basket can be split in two stages, when it accelerates and when it decelerates. So let's analye the first stage:

$n=(\frac{4rev/s+0}{2})(9s)=18rev$

and now let's analyze the second stage, where it decelerates, so we get:

$n=(\frac{0rev/s+4rev/s}{2})(13s)=26rev$

So now that we know how many revolutions the cylindrical basket will take as it accelerates and as it decelerates we can add them to get:

n=18rev+26rev=44rev

So the basket will turn a total of 44 revolutions during this 22s interval.

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3 years ago

Urgent~What type of angles are 1 and 5?

Kitty [74]

Corresponding angles ??

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What is the area of the sector with a central angle of 49° and a radius of 11 cm? Use 3.14 for pi and round your final answer to

olga_2 [115]

Answer:

$\boxed{\text{51.71 cm}^{2}}$

Step-by-step explanation:

If the angle θ is in radians, the formula for the area (A) of a sector of a circle is

A = ½r²θ

If θ is in degrees

$A = \dfrac{1}{2}r^{2}\theta \times \dfrac{\pi \text{ rad}}{180^{\circ}}= \pi r^{2}\times\dfrac{\theta }{360}$

Data:

θ = 49°

r = 11 cm

Calculation:

$\begin{array}{rcl}A& = &3.14\times 11^{2}\times\dfrac{49}{360}\\\\ & = &3.14 \times 121 \times 0.1361\\ & = & \mathbf{51.71}\\\end{array}\\\text{The area of the sector is }\boxed{\textbf{51.71 cm}^{2}}$