Question

Which is an equation of a circle with center (2, -1) that passes through the point (3, 4)?
(x + 2)2 + (y - 1)2 = 13
(x - 2)2 + (y + 1)2 = 26
(x - 2)2 + (y + 1)2 = 13
(x + 2)2 + (y - 1)2 = 26

Answer 1

(x-a)^2+(y-b)^2=r^2
where (a, b) center r radius

Answer 2

distance from center to (3, 4) is sqrt26.

Answer 3

so radius is sqrt26

Answer 4

can you write it now?

Answer 5

i dont get it

Answer 6

ok (x-a)^2+(y-b)^2=r^2
where (a, b) center r radius substitute (x-2)^2+(y+1)^2=(sqrt26)^2

Answer 7

(x - 2)2 + (y + 1)2 = 26

Answer 8

medal plz?