How do you find the center and radius of a circle?

The General Form of the equation of a circle is x² + y² + 2gx +2fy + c = 0. The centre of the circle is (-g, -f) and the radius is √(g² + f² – c). Given a circle in the general form you can complete the square to change it into the standard form. More on this can be found on the Quadratic Equations page Here.

How do you find the equation of a circle?

The formula for the equation of a circle is (x – h)²+ (y – k)² = r², where (h, k) represents the coordinates of the center of the circle, and r represents the radius of the circle. If a circle is tangent to the x-axis at (3,0), this means it touches the x-axis at that point.

Who is the Centre of a circle?

The center of a circle is the point equidistant from the points on the edge. Similarly the center of a sphere is the point equidistant from the points on the surface, and the center of a line segment is the midpoint of the two ends.

How do you write the standard form of a circle?

The standard form of a circle’s equation is (x-h)² + (y-k)² = r² where (h,k) is the center and r is the radius. To convert an equation to standard form, you can always complete the square separately in x and y.

What does the equation of a circle mean?

The equation of a circle is a way to express the definition of a circle on the coordinate plane. If the center of the circle is at the origin of the coordinate plane, the equation is where r is the radius. When the center of the circle is at the point (h,k), the equation becomes .