How do you write the standard form of the equation of the circle with the given the center (0,0), r=12?

1 Answer
Apr 19, 2016

x^2 + y^2 = 12^2x2+y2=122

Explanation:

For a circle centered at (a,b)(a,b) with radius rr, the equation of the circle is given by

(x-a)^2 + (y-b)^2 = r^2(xa)2+(yb)2=r2

This follows from the Pythagoras Theorem. Refer to the diagram below.

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In this case, (a,b) = (0,0)(a,b)=(0,0) and r = 12r=12. Therefore, the equation of the circle is

(x-0)^2 + (y-0)^2 = 12^2(x0)2+(y0)2=122

or after simplifying,

x^2 + y^2 = 144x2+y2=144