Question

Give the coordinates of the circle's center and its radius. (x−1)^2 +(y+8)^2 =16

a. (-1,8); r=4
b. (1,-8); r=16
c. (1,-8); r=4
d. (-1,8); r=16
e. none of these

Answer 1

You must memorize the pattern of the standard circle and the information it provides

centre is (1, -8)
radius = √16 = 4