Graphing Equations of Circles in the Coordinate Plane

What does the 'R' value in the circle's equation represent?

• Diameter of the circle

• Area of the circle

• Radius of the circle

• Circumference of the circle

What does the ordered pair (H, K) in the circle's equation represent?

• The circle's diameter endpoints

• The circle's radius endpoints

• The circle's center point

• The circle's circumference points

In the equation (X - H)^2 + (Y - K)^2 = R^2, changing the sign of H and K affects which aspect of the circle?

• Its radius

• Its diameter

• Its center location

• Its circumference

If a circle's center is at (3, -2) and its radius is 3, what is the correct form of its equation?

• (X + 3)^2 + (Y - 2)^2 = 9

• (X - 3)^2 + (Y - 2)^2 = 9

• X - 3)^2 + (Y + 2)^2 = 9

• (X - 3)^2 + (Y + 2)^2 = 9

For a circle centered at the origin with a radius of 5, what is the standard equation?

• X^2 - Y^2 = 5

• X^2 - Y^2 = 25

• X^2 + Y^2 = 25

• X^2 + Y^2 = 5

Given the equation X^2 + Y^2 = 36, where is the circle centered?

• At (3, 3)

• At (36, 36)

• At (6, 6)

• At the origin (0, 0)

How do you find the radius of a circle from its equation?

• By taking the square root of the R-squared value

• By squaring the R value

• By doubling the R value

• By halving the R-squared value

If an equation of a circle is given as (X - 4)^2 + (Y + 2)^2 = 36, what is the radius of the circle?

• 18

• 6

• 36

• 12

Given the equation (X + 7)^2 + (Y - 3)^2 = 9, what is the center of the circle?

• (7, 3)

• (-7, -3)

• (-7, 3)

• (7, -3)

What is the radius of a circle whose equation is (X + 7)^2 + (Y - 3)^2 = 9?

• 6

• 9

• 18

• 3