Question

Select the correct answer. Which equation represents a circle with center T(5,-1) and a radius of 16 units? A. (x − 5)2 + (y + 1)2 = 16 B. (x − 5)2 + (y + 1)2 = 256 C. (x + 5)2 + (y − 1)2 = 16 D. (x + 5)2 + (y − 1)2 = 256 Reset Next

Answer 1

B.

Explanation:

well, since the generic formula for a circle is

(x - h)² + (y - k)² = r²

with (h, k) being the circumstances of the center of the circle, and r being the radius, it is really just a matter of comparing the data :

h = 5

k = -1

r = 16, r² = 16×16 = 256

it has to be therefore

(x - 5)² + (y + 1)² = 256