What is the standard form of an equation of a circle? Definition and examples


The standard form of an equation of a circle with center (h,k) and radius r is (x - h)2 + (y - k)2 = r2

Circle with center (h,k)

If you put the center at the origin of the coordinate system, the standard form of the equation of the circle is x2 + y2 = r2

How to write the standard form of an equation of a circle


Write an equation of a circle with center (-2, 5) and radius 3

(x - h)2 + (y - k)2 = r2

Substitute 3 for r, -2 for h, and 5 for k

(x - -2)2 + (y - 5)2 = 32

Simplify

(x + 2)2 + (y - 5)2 = 9

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Math words beginning with the letter s

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