Question

Find the equation of the circle that has:
endpoints of the diameter: (2,5) and (4,-1)

Answer 1

Hint: Find the midpoint of the diameter.

Answer 2

wat was the midpoint equation again? xD haha..

Answer 3

Really bro? I mean, really? Do I have to spell everything out for you every time? Some things you should be able to figure out on your own.

Answer 4

hahaok ill check on wikipedia

Answer 5

\[\left(\frac{x_1 + x_2}{2}, \frac{y_1 + y_2}{2}\right)\]

Answer 6

ok for the midpoint i got (-1,2)

Answer 7

That is not correct.

Answer 8

oh wait sorry its late haha i meant (3,2) :)))))))

Answer 9

So that's the center of your circle. Now find the radius.

Answer 10

so i use distance formula using these points?

Answer 11

my teacher got (x-3)^2 + (y-2)^2 = 10 shouldn't it be 25?

Answer 12

the previous question of this said that the radius is 5

Answer 13

@Hero

Answer 14

@binary3i can u help me? ^^

Answer 15

you know the end points
of diameter so mid point of diameter will be the center of circle can you do that?
and radius is the half of diameter so can you also find that using distance between the end points of diameter then dividing it by 2. then using the general equation

Answer 16

@lilfayfay, if the answer was r^2 = 10, then you can assume that the radius was sqrt(10)

Answer 17

Then further prove it to yourself by actually doing the work.

Answer 18

well i get how my teacher got (x-3)^2 + (y-2)^2 but it dont get the (x-3)^2 + (y-2)^2 = 10

Answer 19

@binary3i so how did he get =10??

Answer 20

I just told you how. :/

Answer 21

no it was r^2=25 from the previous question center at (2, -4) and radius of 5.

Answer 22

or does the previous question have nothing to do with this question

Answer 23

(x-h)^2 + (y-k)^2=R^2
where h and k are the midpoints and R is the radius
R is from dividig the diameter by 2
did you used the distance formula for the end points of the diameter

Answer 24

so i do (x-3)^2 + (y-2)^2 = R^2?

Answer 25

Yes bro. Geez, do you pay attention to any of these formulas?

Answer 26

@binary3i so what do i do next

Answer 27

Bro, I explained it to you. When the other guy explains it, you will see that it is r = sqrt(10)
r^2 = 10

Answer 28

but myteacher put (x-3)^2 + (y-2) = 10 and wheredid the 10 come from? From the previous question

Answer 29

\[2R=\sqrt{(4-2)^2 + (-1-5)^2}=\sqrt{2^2 + 6^2)}=\sqrt{4+36}=\sqrt{40}=2\sqrt{10}\]

Answer 30

thats it?

Answer 31

im just finding the equation of the circle

Answer 32

Divide that by 2 to get \sqrt(10)

Answer 33

so the equation of the circle is:\[(x-3)^2 + (y-2)^2 = \sqrt{10}\]?

Answer 34

No bro

For the 10000th time

\[r = \sqrt{10}\]
\[r^2 = 10\]

The formula needs to be written in terms of \(r^2\). Get it?

Answer 35

but the question is only asking me to write the equation of the circle not find the radius BRO

Answer 36

Bro, in order to write the equation of the circle, you need the square of the radius.

Answer 37

yeah so its (x-3)^2 +(y-2)^2 =sqr10 BROOooooooooooo

Answer 38

Bro, it's 10, not sqrt(10). Now you're just being mental.

Answer 39

how is it 10........

Answer 40

Now you want me to explain it to you 10,001 times

Answer 41

see R = sqrt{10}
R^2=10
eqution of circle is
(X-h)^2 + (Y-k)^2= R^2

Answer 42

lol :P xD

Answer 43

@lilfayfay, @binary3i agrees with me.

Answer 44

He just wrote the exact same thing I wrote

\[r = \sqrt{10}\]
\[r^2 = 10\]

Answer 45

yes hero i stand with you

Answer 46

so the answer is \[\sqrt{(x-3)^2 + (y-2)^2} = 10\]

Answer 47

Yes, finally, after all these years....you figure it out. Even though all you needed was two seconds.

Answer 48

why didnt u tell me earlier that I left out the square root

Answer 49

Good question.

Answer 50

............................ :P

Answer 51

Hey bro, I can't correct every single mistake you make. Some things you have to figure out on your own.

Answer 52

no wait it's just (x-3)^2 + (y-2)^2 = 10

Answer 53

Confusing yourself again.

Answer 54

no that's correct, thats what my teacher got

Answer 55

Your teacher doesn't make mistakes?

Answer 56

he does but thats the answer he gave and reviewed with the whole class

Answer 57

Okay bro. Good luck with that. By the way, when I was in school, I corrected my teacher on numerous occasions. If I came to your school, I would correct your teacher as well. Fortunately, I'm not a student anymore. But you are, and when you have the opportunity to correct your teacher, you should. All the students in your class must be afraid of your teacher.

Answer 58

nope it's completely the opposite ^^

Answer 59

lol