Convert Circle Equations into Center Radius Form

Find the center and radius of the circle: (x+2)² + (y-4)² =16

• center: (-2, 4); r = 4

• center: (2, -4); r = 4

• center: (-2, -4); r = 8

• center: (-2, 4); r = 16

In order to convert from general form to center-radius form, you must ___________. 

• Multiply out

• expand

• factor

• complete the square

Convert the equation of the circle from general to standard form.

• A

• B

• C

• D

Determine the center and radius: x² + y² + 14x - 2y = -1

• center= (-7,2) radius= 3

• center= (-7,1) radius= 7

• center= (-4,1) radius= 5

What is the center and radius for a circle with the equation:
(x-4)²+(y+2)²=25

• C:(4, -2), r=5

• C:(-4, 2), r=5

• C:(4, -2), r=25

• C:(-4, 2), r=25

Determine the center and radius:
x² + y² - 10x + 8y -8 = 0

• C = (5,-4) r = 7

• C = (-5,4) r = 7

• C = (-4,5) r = 49

• C = (5,-4) r = 49

What is the coordinates of the centre and the radius of the circle with equation:
(x - a)² + (y - b)² = r² ?

• Centre (a,b)
  Radius = r^2 units

• Centre (-a,-b)
  Radius = r units

• Centre (a,b)
  Radius = r units

• Centre (-a,-b)
  Radius = r^2 units

What are the coordinates of the center and the radius of the circle with equation (x - 4)² + (y - 3)² = 25 ?

• Center (4, 3)

  Radius = 5 units

• Center (4, 3)

  Radius = 25 units

• Center (-4, -3)

  Radius = 25 units

• Center (-4, -3)

  Radius = 5 units

Find the center and radius of the circle: x² + y² + 14x - 2y = -1.

• center = (-7, 2) radius = 3

• center = (-7, 1) radius = 7

• center = (-4, 1) radius = 7

• center = (-4, 2) radius = 3

What is the coordinates of the centre and the radius of the circle with equation:
(x - a)² + (y - b)² = r² ?

• Centre (a,b)
  Radius = r^2 units

• Centre (-a,-b)
  Radius = r units

• Centre (a,b)
  Radius = r units

• Centre (-a,-b)
  Radius = r^2 units