Question

Find the center and radius of the circle represented by the following equation: x squared plus left-parenthesis y plus 4 right-parenthesis squared equals 3.
(1 point)
Responses

center: left-parenthesis 0 comma negative 4 right-parenthesis; r equals Start Root 3 End Root
center: Image with alt text: left-parenthesis 0 comma negative 4 right-parenthesis ; Image with alt text: r equals Start Root 3 End Root

center: left-parenthesis 0 comma negative 4 right-parenthesis; r = 3
center: Image with alt text: left-parenthesis 0 comma negative 4 right-parenthesis ; r = 3

center: left-parenthesis 0 comma 4 right-parenthesis; r equals Start Root 3 End Root
center: Image with alt text: left-parenthesis 0 comma 4 right-parenthesis ; Image with alt text: r equals Start Root 3 End Root

center: left-parenthesis 0 comma 4 right-parenthesis; r = 3

1 answer

To find the center and radius of the circle defined by the equation \( x^2 + (y + 4)^2 = 3 \), we can compare it to the standard form of a circle's equation, which is:

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

where \((h, k)\) is the center of the circle and \(r\) is the radius.

Looking at the equation \( x^2 + (y + 4)^2 = 3 \):

  1. Identifying the center:

    • The expression \( (y + 4)^2 \) can be rewritten as \( (y - (-4))^2 \). Thus, we can determine \(k = -4\) and \(h = 0\).
    • So, the center is \((0, -4)\).
  2. Identifying the radius:

    • The right side of the equation is \(3\), which corresponds to \(r^2\). Therefore, \(r^2 = 3\).
    • To find \(r\), we take the square root: \[ r = \sqrt{3} \]

Thus, the center of the circle is \((0, -4)\) and the radius is \(\sqrt{3}\).

Based on the options provided, the correct answer is:

center: (0, -4); r = √3