Question

The equation of a circle is x2 + (y – 10)2 = 16.

The radius of the circle is units.

The center of the circle is at .

Answer 1

4 units

(0,10)

Answer 2

When graphing a circle, the following formula is used:


`(x - h)^(2) + (y - k)^(2) = r^(2)`

h and k refer to the center of the circle, which is found at (h,k).

To find the radius of the circle, square root the right side:


`√(16) = 4`

The radius of the circle is 4 units.

Look at the equation to find h and k. There is no h value represented, so h will equal 0. 10 is subtracted from y, so k is 10. The center of the circle is at (0,10).