To derive the equation of a circle in standard form, we use the formula:
\[ (x - h)^2 + (y - k)^2 = r^2 \]
where \((h, k)\) is the center of the circle and \(r\) is the radius.
Given:
- Center \((h, k) = (-2, 0)\)
- Radius \(r = 7\)
Substituting these values into the formula:
- Substitute \(h = -2\) and \(k = 0\):
\[ (x - (-2))^2 + (y - 0)^2 = 7^2 \] This simplifies to: \[ (x + 2)^2 + y^2 = 49 \]
Therefore, the equation of the circle in standard form is:
\[ (x + 2)^2 + y^2 = 49 \]
So the correct response is: \[ \text{(x+2) }^2 + y^2 = 49 \]