equation of a circle_Q

Write the equation at the origin with radius 6.  

• x^2 + y^2 = 6
• x^2 + y^2 = 36
• x  + y = 6
• x + y = 36

What is the equation for the circle, if it has diameter endpoints at (3,-4) and (-5,-4)?

• (x+1)² + (y-4)² = 4

• (x+1)² + (y+4)² = 16

• (x-1)² + (y-4)² = 16

• (x+1)² + (y+4)² = 4

What are the coordinates of the center and the radius of the circle with an 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

A circle has the equation  x² + y² - 12x + 8y + 3 = 0.  Use completing the square to 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

Which graph represents the circle:

x² + (y - 6)² = 9

• A

• B

• C

• D

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

What is the radius of the circle with this equation of  (x-5)²+(y+7)²=8?

• 4
• 8
• 4√2
• 2√2

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

In the equation for a circle, (x-h)²+(y-k)²= r², what part of the circle do the h, k and r represent?

• r is the hypotenuse, h and k are points on the circle

• r is the radius, h and k are points on the circle

• r is the roundness, h and k represent the center

• r is the radius, h and k represent the center

Given the equation of a circle is (x-7)²+(y+3)²=36, what is the radius of the circle?

• 6

• 3

• 7

• 36