Get the information you need with the help of IDNLearn.com's expert community. Join our community to receive prompt and reliable responses to your questions from experienced professionals.

Select the correct answer.

Which equation represents a circle with a center at [tex]$(-5,5)$[/tex] and a radius of 3 units?

A. [tex]$(x-5)^2+(y+5)^2=9$[/tex]
B. [tex][tex]$(x+5)^2+(y-5)^2=6$[/tex][/tex]
C. [tex]$(x+5)^2+(y-5)^2=9$[/tex]
D. [tex]$(x+5)^2+(y-5)^2=3$[/tex]
E. [tex][tex]$(x-5)^2+(y+5)^2=3$[/tex][/tex]


Sagot :

To determine the equation of a circle, we use the standard form of the circle equation:

[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 the radius.

In this problem, the center of the circle is given as [tex]\((-5, 5)\)[/tex] and the radius is given as [tex]\(3\)[/tex] units. Let's substitute these values into the standard form equation:

1. Substitute the center coordinates: The center [tex]\((h, k)\)[/tex] is [tex]\((-5, 5)\)[/tex], so we have:
- [tex]\(h = -5\)[/tex]
- [tex]\(k = 5\)[/tex]

2. Substitute the radius: The radius [tex]\(r\)[/tex] is [tex]\(3\)[/tex], so [tex]\(r^2 = 3^2 = 9\)[/tex].

Now, substitute [tex]\(h\)[/tex], [tex]\(k\)[/tex], and [tex]\(r^2\)[/tex] into the standard form equation:

[tex]\[ (x - (-5))^2 + (y - 5)^2 = 3^2 \][/tex]

Simplify the terms:

[tex]\[ (x + 5)^2 + (y - 5)^2 = 9 \][/tex]

Therefore, the equation that represents a circle with a center at [tex]\((-5, 5)\)[/tex] and a radius of 3 units is:
[tex]\[ (x + 5)^2 + (y - 5)^2 = 9 \][/tex]

Based on the given choices, the correct answer is:

C. [tex]\((x + 5)^2 + (y - 5)^2 = 9\)[/tex]