Question

what is the center of a circle represented by the equation $(x+9)^2+(y-6)^2=10^2$?
$(-9,6)$
$(-6,9)$
$(6,-9)$
$(9,-6)$

Explanation:

Step1: Recall circle standard form

The standard equation of a circle is $$(x-h)^2+(y-k)^2=r^2$$, where $(h,k)$ is the center, $r$ is radius.

Step2: Match given equation to standard form

Rewrite the given equation: $(x-(-9))^2+(y-6)^2=10^2$. Compare to standard form, so $h=-9$, $k=6$.

Answer:

(-9,6)