1. **State the problem:** We are given the equation of a circle:
$$x^2 + y^2 - 14x + 10y + 49 = 0$$
We need to find the coordinates of the center $(x, y)$ and then calculate $x + y$.
2. **Formula and rules:** The general form of a circle's equation is:
$$ (x - h)^2 + (y - k)^2 = r^2 $$
where $(h, k)$ is the center and $r$ is the radius.
To find the center, we complete the square for both $x$ and $y$ terms.
3. **Complete the square for $x$:**
Group $x$ terms:
$$x^2 - 14x$$
Take half of $-14$, which is $-7$, and square it:
$$(-7)^2 = 49$$
Add and subtract 49 inside the equation to complete the square:
$$x^2 - 14x + 49 - 49$$
This becomes:
$$(x - 7)^2 - 49$$
4. **Complete the square for $y$:**
Group $y$ terms:
$$y^2 + 10y$$
Take half of $10$, which is $5$, and square it:
$$5^2 = 25$$
Add and subtract 25 inside the equation:
$$y^2 + 10y + 25 - 25$$
This becomes:
$$(y + 5)^2 - 25$$
5. **Rewrite the original equation:**
$$x^2 + y^2 - 14x + 10y + 49 = 0$$
Substitute the completed squares:
$$ (x - 7)^2 - 49 + (y + 5)^2 - 25 + 49 = 0 $$
Simplify constants:
$$ (x - 7)^2 + (y + 5)^2 - 25 = 0 $$
Add 25 to both sides:
$$ (x - 7)^2 + (y + 5)^2 = 25 $$
6. **Identify the center and radius:**
Center: $(7, -5)$
Radius: $\sqrt{25} = 5$
7. **Calculate $x + y$:**
$$7 + (-5) = 2$$
**Final answer:** $2$ (Option C)
Circle Center Sum 8Eeb4D
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