1. What is the equation of the circle whose center lies at the origin but whose
radius is 5?
a. x2 + y2 = 25
c. x2 + y2 = 5
b. x2 + y2 =
d. x2 + y2
= 0
2. A circle has center at (1, 0) and a radius of 4, what is the equation of the
circle?
a. (x + 1)2 + y2 = 0
C. (x - 1)2 + y2 = 16
b. (x - 1)2 + y2 = 4
d. (x + 1)2 + y2 = 16
3. A circle has center at (-1,2) and a radius of 3, what is the equation of the
circle?
a. (x + 1)2 + (y - 2)2 = 9 c. (x + 1)2 + (y + 2)2 = 9
b. (x - 1)2 + (y-2)2 9
d. (x - 1)2 + (y + 2)2 = 9​