The Equation of a Circle

Form of the equation
(x - h)[sup]2 [/sup]+ (y - k)[sup]2[/sup] = R[sup]2[br][br][/sup]where the center is at (h, k) and the radius is R.[br][br]Remember - the signs of the center are switched !
Try it! Drag the sliders to change the center and radius of the circle. use the + and - tools to zoom in and out.
Answer these !
1. What is the radius if the circle whose equation is (x - 1)[sup]2 [/sup]+ (y - 4)[sup]2 [/sup]= 25
What is the center of the circle whose equation is (x + 3)[sup]2 [/sup]+ (y - 5)[sup]2[/sup] = 36
Close

Information: The Equation of a Circle