What is the center of a circle represented by the equation [tex](x+9)^2 + (y-6)^2 = 10^2[/tex]?

A. [tex](-9, 6)[/tex]
B. [tex](-6, 9)[/tex]
C. [tex](6, -9)[/tex]
D. [tex](9, -6)[/tex]



Answer :

To determine the center of the circle represented by the equation [tex]\((x+9)^2 + (y-6)^2 = 10^2\)[/tex], we need to understand the standard form of a circle's equation. The general form of a circle's equation is:

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

where [tex]\((h, k)\)[/tex] is the center of the circle and [tex]\(r\)[/tex] is its radius.

Now, let's compare the given equation with the standard form step-by-step:

1. Identify the parts of the standard form in the given equation:

[tex]\[ (x + 9)^2 + (y - 6)^2 = 10^2 \][/tex]

2. Recall that in the standard form [tex]\((x - h)\)[/tex] and [tex]\((y - k)\)[/tex], [tex]\(h\)[/tex] and [tex]\(k\)[/tex] are the coordinates of the center, but with signs opposite to those in the equation due to the form [tex]\((x - h)\)[/tex] and [tex]\((y - k)\)[/tex].

3. For [tex]\(x\)[/tex]:
- In [tex]\((x - h)^2\)[/tex], we have [tex]\((x + 9)^2\)[/tex] in our given equation.
- This indicates [tex]\(x - h = x + 9\)[/tex], which means [tex]\(h = -9\)[/tex].

4. For [tex]\(y\)[/tex]:
- In [tex]\((y - k)^2\)[/tex], we have [tex]\((y - 6)^2\)[/tex] in our given equation.
- This indicates [tex]\(y - k = y - 6\)[/tex], which means [tex]\(k = 6\)[/tex].

So, the center [tex]\((h, k)\)[/tex] of the circle is [tex]\((-9, 6)\)[/tex].

Thus, the correct answer is:

[tex]\[ (-9, 6) \][/tex]

This result matches the provided options, confirming that the center of the circle is [tex]\((-9, 6)\)[/tex].