NEED HELP question number 1 9.05^-10.05 Question number 2 -.25^.75

What is the area of a circle whose equation is (x-3)² + (y + 1) ² =81?

kupik [55]

Okay, first, given the equation, we need to find out what the radius of the circle is. Let us state the general equation of a circle:

$\frac{(x-x_{1})^2}{r^2}+ \frac{(y-y_{1})_^2}{r^2}=1$

Where $(x_{1}, y_{1})$ is the centre of the circle. In this case, we don't need to know the centre. Just the radius.

Let us start by converting the equation into standard for, which I typed above. Divide both sides by 81.

$\frac{(x-3)^2}{81}+ \frac{(y+1)^2}{81}=1$

Great! We now know the radius of the circle. It is $\sqrt{81}$ because it is the bottom fraction. Now we know that the radius is 9.

So now lets input this into the area of circle formula:

$A=πr^2$

Now we insert our radius.

$A=9^2π$

$=A=81π$

You can convert that into a decimal if you wish.

Hope this helped!

~Cam943, Moderator

4 0

4 years ago

The function f(x) is given by the set of ordered pairs.

JulsSmile [24]

Step-by-step explanation:

incomplete question

you didnt give any choice to choose from

8 0

3 years ago

The amount of money in a savings account after t years is represented by the function f(t)=500(1.015)^t. What does the value 500

MaRussiya [10]

Answer:

Find out the what does the value 500 represent in this situation .

To prove

As given

The amount of money in a savings account after t years is represented by the function.

$f(t)=500(1.015)^{t}$

Exponential function for amount is given by .

$Amount = a (1 + r)^{t}$

Wher a is the initial value, r is the rate in decimal form and t is the time.

Compare the functions

$f(t)=500(1.015)^{t}$

and

$Amount = a (1 + r)^{t}$

Thus a = 500

Therefor $500 is the initial value .

4 0

3 years ago

Two skateboarders, Ron and Bob, are traveling in opposite directions.Ton travels at 8 feet per second and bob travels at 10 feet

omeli [17]

Time taken before they are 2640 feet is 146.67 seconds

Solution:

The distance is given by formula:

$distance = speed \times time$

Ton travels at 8 feet per second

Let us assume, time taken = t

speed = 8 feet per second

Then, distance is given as:

Distance covered by Ton = 8t

Bob travels at 10 feet per second

Then, distance is given as:

Distance covered by Bob = 10t

How long will it take before they are 2640 feet

Which means,

Distance covered by Ton + Distance covered by Bob = 2640

$8t + 10t = 2640\\\\18t = 2640\\\\Divide\ both\ sides\ of\ equation\ by\ 18\\\\t = 146.67$

Thus time taken before they are 2640 feet is 146.67 seconds

<h3>Method 2:</h3>

Since trains are moving in opposite directions, their speeds must be added

speed = 8 + 10 = 18 feet per second

Given distance = 2640 feet

Therefore, time taken is:

$time = \frac{distance}{speed}\\\\time = \frac{2640}{18} = 146.67 \text{ second }$

Thus time taken before they are 2640 feet is 146.67 seconds

4 0

4 years ago

the graph shows rate at which an oven preheats when turned on. what is the unit rate and what does it represent?

zvonat [6]

Answer:

c

Step-by-step explanation:

i dont know

4 0

4 years ago

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