Equation of a Circle

What does (h,k) standard for in the standard circle equation?

• (h,k) is the center of the circle

• (h,k) is a point on the circle.

• (h,k) is the radius of the circle

• (h,k) is the diameter of the circle

What does "h" stand for in (h,k)?

• h is the radius of the circle

• h is the distance of the circle

• h is the y coordinate of the center

• h is the x coordinate of the center

What does the "k" in (h,k) stand for?

• k is the y coordinate of the center

• k is the x coordinate of the center

• k is the radius of the circle

• k is the distance of the circle

What does the r in the standard equation stand for?

• r is the distance of the circle

• r is the radius of the circle

• r is the x coordinate of the center of the circle

• r is the y coordinate of the center 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

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

In the equation (x-3)²+(y-2)²=16, the center of the circle is...

• (3,2)
• (-3, -2)
• (-2, -3)
• (2, 3)

In the equation (x+2)²+(y-3)²=4, the radius of the circle is...

• 4
• 2
• 3
• 16

Write the equation of a circle with center (h,k) and radius r.

• x^2 + y^2  = r^2
• (x + h)^2 +  (y + h)^2 = r^2
• (x - h)^2 + (y - k)^2 = r^2
• (x - h)^2 - (h - k)^2 = r

What is the equation of this circle?

• (x + 3)² + (y - 1)² = 9
• (x - 3)² + (y + 1)² = 9
• (x - 3)² + (y + 1)² = 3
• (x + 3)² + (y - 1)² = 3