Circle Equations Complete the Square

What is the standard equation of a circle?

• (x-k)² + (y-h)² = r²

• (x+h)² + (y+k)² = r²

• (x-h)² + (y-k)² = r²

• (k-x)² + (h-y)² = r²

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

• Multiply out

• expand

• factor

• complete the square

In the equation (x+2)²+(y+3)²=49, the radius of the circle is...

• 14

• 98

• 7

• 49

What is the equation of the circle?

Write the equation of a circle with center (7, 0) with radius 3.

• (x - 7)² + y² = 9

• x² + (y -7)² = 9

• (x - 7)² + y² = 3

• x² + (y -7)² = 3

• A
• B
• C
• D

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 - 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 equation of the circle, with center (4,2) and radius 5 units?

• (x + 4)^2 + (y + 2)^2 = 25

• (x + 4)^2 + (y + 2)^2 = 5

• (x - 4)^2 + (y - 2)^2 = 5

• (x - 4)^2 + (y - 2)^2 = 25