Graphing Circles

1.  Find the equation of the circle centered at the origin, with a radius of 4.

a].  x² + y² = 16

b].  x² + y² = 4

c].  x² + y² = 2

2.     Find the equation of the circle centered at (-4, 2) with a radius of 1.

a].   (x - 4)² + (y + 2)² = 1

b].  (x - 4)² + (y - 2)² = 1

c].   (x + 4)² + (y - 2)² = 1

3.    What is the center and radius of the circle represented by (x - 5)² + (y - 1)² = 5?

a].   Center = (5, 1); Radius = 5.

b].   Center = (5, 1); Radius = .

c].   Center = (5, 1); Radius = 25.

4.  Find the center and radius of the equation represented by x² + (y - 3)² = 16? 

a]. Center = (0, 3); Radius = 4.

b]. Center = (0, -3); Radius = 4.

c]. Center = (0, 3); Radius = 2.

5. Find the center and radius of the equation represented by (x - 4)² + (y + 2)² = 81? 

a].  Center = (4, -2); Radius = 3.

b]. Center = (4, -2); Radius = 9.

c].  Center = (-4, 2); Radius = 9.