General and Standard Equation of a Circle

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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 is the coordinates of the centre and the radius of the circle with equation:
(x - 1)² + (y - 2)² = 3² ?

• Centre (-1,-2)
  Radius = 3 units

• Centre (1,2)
  Radius = 3 units

• Centre (-1,-2)
  Radius = 9 units

• Centre (1,2)
  Radius = 9 units

What is the coordinates of the centre and the radius of the circle with equation:
(x - 4)^2 + (y - 3)^2 = 25^ ?

• Centre  (4,3)
  Radius = 5 units

• Centre  (4,3)
  Radius = 25 units

• Centre  (-4,-3)
  Radius = 25 units

• Centre  (-4,-3)
  Radius = 5 units

What is the coordinates of the centre and the radius of the circle with equation:
(x + 2)^2 + (y + 5)^2 = 16 ?

• Centre  (2,5)
  Radius = 16 units

• Centre (2,5)
  Radius = 4 units

• Centre (-2,-5)
  r = 16 units

• Centre (-2,-5)
  Radius = 4 units

A circle has the equation x² + y² - 12x + 8y + 3 = 0. Write the equation in standard form.

• (x - 6)² + (y + 4)² = 49

• (x + 4)² + (y - 6)² = 49

• (x - 6)² + (y + 4)² = 55

• x² + y² = 55

The equation of a circle is x² + y² + 6x - 12y + 20 = 0. Write the equation in standard form.

• (x - 3)² + (y + 6)² = 25

• (x + 3)² + (y - 6)² = 25

• (x - 3)² + (y + 6)² = 45

• (x + 3)² + (y - 6)² = 5

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

A circle has the equation x² + y² + 10x - 4y + 20 = 0. Write it in standard form.

• (x - 5)² + (y + 2)² = 9

• (x + 5)² + (y - 2)² = 3

• (x + 5)² + (y - 2)² = 9

• (x - 5)² + (y + 2)² = 3

What is the center for the circle with this equation x² + y² + 4x + 6y - 36 = 0?

• (-2, 5)

• (2, 7)

• (-2, -7)

• (-2, -3)