Select the correct answer.

Which point lies on the circle represented by the equation [tex]$(x+7)^2+(y-10)^2=13^2$[/tex]?

A. [tex]$(5,12)$[/tex]
B. [tex][tex]$(-7,-3)$[/tex][/tex]
C. [tex]$(-6,-10)$[/tex]
D. [tex]$(6,23)$[/tex]



Answer :

To determine which point lies on the circle given by the equation [tex]\((x+7)^2 + (y-10)^2 = 13^2\)[/tex], we need to check the distance of each point from the center of the circle and see if it equals the radius of the circle.

The center of the circle is [tex]\((-7, 10)\)[/tex] and the radius is 13.

We will calculate the distance of each point from the center of the circle:

1. For point [tex]\((5, 12)\)[/tex]:
[tex]\[ \sqrt{(5 + 7)^2 + (12 - 10)^2} = \sqrt{12^2 + 2^2} = \sqrt{144 + 4} = \sqrt{148} \approx 12.17 \][/tex]

2. For point [tex]\((-7, -3)\)[/tex]:
[tex]\[ \sqrt{(-7 + 7)^2 + (-3 - 10)^2} = \sqrt{0^2 + (-13)^2} = \sqrt{169} = 13 \][/tex]

3. For point [tex]\((-6, -10)\)[/tex]:
[tex]\[ \sqrt{(-6 + 7)^2 + (-10 - 10)^2} = \sqrt{1^2 + (-20)^2} = \sqrt{1 + 400} = \sqrt{401} \approx 20.02 \][/tex]

4. For point [tex]\((6, 23)\)[/tex]:
[tex]\[ \sqrt{(6 + 7)^2 + (23 - 10)^2} = \sqrt{13^2 + 13^2} = \sqrt{169 + 169} = \sqrt{338} \approx 18.38 \][/tex]

Comparing the distances calculated:

- Distance for [tex]\((5, 12)\)[/tex] is approximately [tex]\(12.17\)[/tex], not equal to 13.
- Distance for [tex]\((-7, -3)\)[/tex] is exactly [tex]\(13\)[/tex], which is equal to 13.
- Distance for [tex]\((-6, -10)\)[/tex] is approximately [tex]\(20.02\)[/tex], not equal to 13.
- Distance for [tex]\((6, 23)\)[/tex] is approximately [tex]\(18.38\)[/tex], not equal to 13.

Therefore, the point that lies on the circle [tex]\((x+7)^2 + (y-10)^2 = 13^2\)[/tex] is [tex]\((-7, -3)\)[/tex].

The correct answer is:
B. [tex]\((-7, -3)\)[/tex]