Unit 8 Test Review

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 = 3^2 ?

• 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 + 3)^2 + (y + 1)^2 = 2^2 ?

• Centre  (-3,-1)
  Radius = 4 units
• Centre  (3,1)
  Radius = 2 units
• Centre  (-3,-1)
  Radius = 2 units
• Centre  (3,1)
  Radius = 4 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

What is the coordinates of the centre and the radius of the circle with equation:
(x - 5)^2 + (y + 3)^2 = 36 ?

• Centre (5,-3)
  Radius = 6 units
• Centre (-5,3)
  Radius = 6 units
• Centre (-5,3)
  Radius = 36 units
• Centre (5,-3)
  Radius = 36 units

What is the coordinates of the centre and the radius of the circle with equation:
(x + 7)^2 + (y - 6)^2 = 64 ?

• Centre (7,-6)
  Radius = 8 units
• Centre (-7,6)
  Radius = 64 units
• Centre (-7,6)
  Radius = 8 units
• Centre (7,-6)
  Radius = 64 units

What is the equation of the circle, with centre (a,b) and radius r units?

• (x - a)^2 + (y - b)^2 = r^2 
• (x + a)^2 + (y + b)^2 = r^
• (x - a)^2 + (y - b)^2 = r^
• (x + a)^2 + (y + b)^2 = r^2 

What is the equation of the circle, with centre (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

What is the equation of the circle, with centre (3,8) and radius 4 units?

• (x - 3)^2 + (y - 8)^2 = 4
• (x - 3)^2 + (y - 8)^2 = 16
• (x + 3)^2 + (y + 8)^2 = 16
• (x + 3)^2 + (y + 8)^2 = 4