What is the standard form of the equation of a circle?
A circle is a set of points (x, y) which are a fixed distance r, the radius, away from a fixed point (h, k), the center.
The equation of the circle in standard form is
(x - h)2
+ (y - k)2
If a circle is given in general form then we must complete the square on the x and y parts of the equation to rewrite it in standard form.
Conic Sections: The Circle
In this video, you will learn how to identify the equation of a circle, how to write the standard form of a circle from the general form and how to graph a circle.
Conic Sections - Circle Part 1 of 2
Intuitive Math Help Circles
Conic Sections - Circle Part 2 of 2
Circles Intuitive Math Help
This video covers writing equations of circles given information like the radius, center, or a point the circle goes through and the center.
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