Question

(x+4)^2+(y-9)^2=81
What is the center of this? And can anyone explain how to do the center?

Answer 1

(-4, 9)

Explanation:

Given equation of circle is:

`(x + 4)^(2) + {(y - 9)}^(2) = 81 \\ equating \: it \: with \\ (x - h)^(2) + {(y - k)}^(2) = r^2 \\ - h = 4 \implies \: h = - 4\\ - k= - 9 \implies \: k = 9 \\ \therefore \: center \: (h, \: k) = ( - 4, \: 9) \\`