Question

An equation of a circle is given as (x + 6)^2 + (y − 7)^2 = 81. Find the center and radius of the circle.

Answer 1

(-6, 7), r=9

Explanation:

The opposite of the number next to the x is -6, the opposite of the number next to the y is 7. The square root of the number on the right (81) is 9, so 9 is the radius.