Question

question 1 of 25

the equation below describes a circle. what are the coordinates of the center of the circle?

\\((x + 5)^2 + (y + 7)^2 = 21^2\\)

a. (-5, 7)
b. (5, 7)
c. (-5, -7)
d. (5, -7)

Explanation:

Identify standard equation of a circle

$$ (x - h)^2 + (y - k)^2 = r^2 $$

Match given equation to standard form

$$ (x - (-5))^2 + (y - (-7))^2 = 21^2 $$

Extract center coordinates

$$ (h, k) = (-5, -7) $$

Answer:

• A. (-5, 7)
• B. (5, 7)
• C. (-5, -7) (Correct answer)
• D. (5, -7)