Question

A circle has the equation 4(x-4)^2+4y^2=36
find the center and radius

Answer 1

Divide both sides by 4, what do you get?

Answer 2

@teresa65

Answer 3

I am sorry but I have a hard time understanding circles

Answer 4

Hmm, that's just division only...

Answer 5

my brain is fried- I have been at this for three hours

Answer 6

Simple division...
\[\frac{4(x-4)^2+4y^2}{4}=\frac{36}{4}\]Simplify it, what do you get?

PS: Don't worry. I had the experience of spending more than 3 hours on 1 math question. And this one is not that hard!

Answer 7

Thanks!!!!

Answer 8

Thanks?! It's not done yet....

Answer 9

sorry

Answer 10

You need not say sorry.......
So, where are you stuck at now?

Answer 11

Finding the radius and center. Algebrs was my favourite subject in high school but I have been out for 38 years

Answer 12

what do you get for this: \(\frac{4(x-4)^2+4y^2}{4}=\frac{36}{4}\) ?

Answer 13

that is where I am stuck. I cannot seem to make any sense of this. I am having trouble with 4(x-4)^2/4

Answer 14

Do i do the multiplication first then the division

Answer 15

am I stupid or what? lol

Answer 16

Just division.
\[\frac{4(x-4)^2}{4} = (x-4)^2\]

Answer 17

ok now I see

Answer 18

Can you simplify \(\frac{4(x-4)^2+4y^2}{4}=\frac{36}{4}\) now?

Answer 19

(x-4)^2 + y^2=9

Answer 20

Yup!!!
Now, express the equation in the form \((x-h)^2 + (y-k)^2 = r^2\)

Answer 21

would it be (x-2)^2 + (y-0)^2=3

Answer 22

my brainis definitely gone

Answer 23

Not really. ^2 after 3 and things in the first bracket doesn't change.
It is (x-4)^2 + (y-0)^2=3^2

Answer 24

Next, for a equation \((x-h)^2 + (y-k)^2 = r^2\),
(h,k) are the coordinates of centre, r is the radius
Can you identify the values of h, k and r?

Answer 25

h=-4, k=0, and r=3?

Answer 26

h is 4 ... not -4
Others are correct.
Now can you get the centre and radius?

Answer 27

Yes I can thanks so much for the help!

Answer 28

Welcome!