How to write the equation of a circle given a circle on a graph

The video tutorial explains the equation of a circle, focusing on the components X, Y, H, K, and R. It describes how X and Y represent points on the circle, while H and K denote the center, and R is the radius. The tutorial guides students through identifying the center and radius of a circle and using these to formulate the circle's equation.

What do the variables X and Y represent in the equation of a circle?

• The diameter of the circle

• The radius of the circle

• Points on the circle

• The center of the circle

In the context of a circle's equation, what do the variables H and K represent?

• The circumference of the circle

• The center of the circle

• The diameter of the circle

• The radius of the circle

How is the radius of a circle defined in relation to its center?

• The distance from the center to any point on the circle

• The distance around the circle

• The distance across the circle through the center

• The distance from the center to the circumference

What is the next step after identifying the center and radius of a circle to find its equation?

• Plug in the values of H, K, and R into the equation

• Determine the area

• Calculate the circumference

• Find the diameter

If the center of a circle is at (0, -2) and the radius is 3, what is the equation of the circle?

• X^2 + Y^2 = 9

• (X + 2)^2 + Y^2 = 9

• X^2 + (Y + 2)^2 = 9

• (X - 0)^2 + (Y - 2)^2 = 9