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2 years ago

Write the equation of a circle that has a center of (-8, 0) and a diameter of 8.

Mathematics

1 answer:

Sveta_85 [38]2 years ago

8 0

Answer:

(x+8)^2+y^2=16

Step-by-step explanation:

The equation for a circle in center-radius form is

(x-h)^2+(y-k)^2=r^2

where (h,k) is the center and r is the radius.

We are given the diameter is 8 so the radius is 8/2=4.

We are also given (h,k) is (-8,0).

The equation for the circle is

(x--8)^2+(y-0)^2=4^2

(x+8)^2+y^2=16

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HELP PLEASE! Write a quadratic function that passes through the point (-1,9), has an axis of symmetry of x=-3 and a minimum valu

xxTIMURxx [149]

Answer:

$y = \frac{1}{2}x^{2} - 3x + 11.5$

Step-by-step explanation:

Vertex form of a quadratic equation;

$y = a( x - h )^{2} + k$

Vertex of the parabolas (h, k)

The vertex of the parabola is either the minimum or maximum of the parabola. The axis of symmetry goes through the x-coordinate of the vertex, hence h = -3. The minimum of the parabola is the y-coordinate of the vertex, so k= 7. Now substitute it into the formula;

$y = a ( x + 3 ) ^{2} + 7$

Now substitute in the given point; ( -1, 9) and solve for a;

$9 = a( (-1 ) + 3)^2 + 7\\9 = a (2)^{2} + 7\\9 = 4a + 7\\-7 -7\\2 = 4a\\\frac{1}{2} = a\\$

Hence the equation in vertex form is;

$y = \frac{1}{2}(x - 3)^{2} + 7$

In standard form it is;

$y = \frac{1}{2}x^{2} - 3x + 11.5$

7 0

2 years ago

HELP ASAP! The number of entertainment websites in 1995 wass 54. By 2004 there were 793 entertainment website..

AleksandrR [38]

<h3>Answer: Choice A. 82 websites per year</h3>

=============================================================

How I got that answer:

We have gone from 54 websites to 793 websites. This is a change of 793-54 = 739 new websites. This is over a timespan of 2004-1995 = 9 years.

Since we have 739 new websites over the course of 9 years, this means the rate of change is 739/9 = 82.1111... where the '1's go on forever. Rounding to the nearest whole number gets us roughly 82 websites a year.

----------

You could use the slope formula to get the job done. This is because the slope represents the rise over run

slope = rise/run

The rise is how much the number of websites have gone up or down. The run is the amount of time that has passed by. So slope = rise/run = 739/9 = 82.111...

In a more written out way, the steps would be

slope = rise/run

slope = (y2-y1)/(x2-x1)

slope = (793 - 54)/(2004 - 1995)

slope = 739/9

slope = 82.111....

3 0

3 years ago

if you rolled a die, what is the probability that you would roll a 4? (simplified fraction as an answer pls)

Ipatiy [6.2K]

The answer would probably be 2/5

4 0

3 years ago

Modeling Exponential Growth and Decay In Exercises 119 and 120, Find the exponential function

Lubov Fominskaja [6]

Answer:

There is no exponential function passing through (1,1) and (5,5).

Step-by-step explanation:

We have the following exponential function

$y = Ce^{kt}$

The function passes through these two points:

(1,1): This means that when t = 1, y = 1

(5,5): This means that when t = 5, y = 5.

(1,1)

$y = Ce^{kt}$

$Ce^{k} = 1$

$e^{k} = \frac{1}{C}$

(5,5)

$y = Ce^{kt}$

$5Ce^{k} = 1$

$Ce^{k} = \frac{1}{5}$

From above, we have that:

$e^{k} = \frac{1}{C}$

$C\frac{1}{C} = \frac{1}{5}$

$1 = \frac{1}{5}$

1 cannot be equal to 1/5, so this is wrong.

This means that there is no exponential function passing through (1,1) and (5,5).

5 0

3 years ago

Need the answer ASAP

Evgesh-ka [11]

Anwser:

22.5 or 5/22 or 30

Step-by-step Explanation:

-2 and -2
SSS
-2+-2= -4

-4 x 30= -120

-120 divided by 4 is 30
but that’s not a fraction so you do

22.5 or 5/22

-2 x -2 x 30=

7 0

3 years ago