Question

A circle is shown on the coordinate plane below.

http://learn.flvs.net/webdav/assessment_images/educator_geometry_v14/pool_Geom_3641_0802_07/image0034e849df3.gif

What is the equation of this circle?

x2 + (y + 1)2 = 4

x2 + (y – 1)2 = 2

x2 + (y + 1)2 = 2

x2 + (y – 1)2 = 4

Answer 1

@ParthKohli @Hero

Answer 2

@ganeshie8

Answer 3

I think it's the first one

Answer 4

is it the first choice? I'm just double checking

Answer 5

check again :)

Answer 6

why is it the last one?

Answer 7

wouldnt it be 2^2=4 so its the first one? Dont you have to add not subtract?

Answer 8

general form of equation is :
(x-h)^2 + (y-k)^2 = r^2

can you tell whats the center (h, k) and radus r, from the figure ?

Answer 9

yeah radius you got it correct !!

Answer 10

yes, the center is 0,1 and the radius is 2

Answer 11

wait.... so which one is it?

Answer 12

1st or last?

Answer 13

center = (h, k) = (0, 1)


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

Answer 14

plug in h and k values

Answer 15

(x-0)^2 + (y-1)^2 = 2^2

x^2 + (y-1)^2 = 4

Answer 16

so the first one?

Answer 17

does that help/make sense ?