Question

Circle P has a radius of 8 units with center P at (-2, 1). Which equation defines circle P?
(x + 2)2 + (y – 1)2 = 8

(x – 2)2 + (y + 1)2 = 8

(x + 2)2 + (y – 1)2 = 64

(x – 2)2 + (y + 1)2 = 64

Answer 1

equation of a circle is

(x - a)^2 + (y - b)^2 = r^2

where (a,b) is center and r = radius

so if the x coordinate of circle = -2 then first term is (x + 2)^2

Answer 2

is it (x + 2)2 + (y – 1)2 = 8 ?

Answer 3

not quite - its r^2

Answer 4

(x + 2)2 + (y – 1)2 = 64 ?

Answer 5

yes

Answer 6

thanks !