Question

Given the equation of a circle below, determine the center and radius of the circle.

(x+5)^2+y^2=36

Answer 1

9514 1404 393

Answer:

• center: (-5, 0)
• radius: 6

Explanation:

Compare the given equation to the standard form equation for a circle with center (h, k) and radius r.

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

You see that ...

-h = +5 ⇒ h = -5

-k = 0 ⇒ k = 0

r^2 = 36 ⇒ r = √36 = 6

The center is (h, k) = (-5, 0), and the radius is r = 6.