# Completing the square circle formula

STANDARD G.GPE.A.1 GEO/AII. Derive the equation of a circle of given center and radius using the Pythagorean Theorem; complete the square to find the center and radius of a circle given by an equation. Page 1 of 7 EQUATION OF A CIRCLE (COMPLETING THE SQUARE) Unfortunately, you may not always be given the equation of the circle in the form (x – a)2 + (y – b)2 = r2.They can be written by using a method called completing the square. (x h)2 + (y k)2 = r2 is the equation of a circle of radius rcentered at the point (h;k). Using the method of completing the square (twice) ﬁnd the radius and center of the circle given by the equation x 2+y +8x 6y+21 = 0. Logs with fractions, linier combinations algebra, radical form converter, cube of trinomial formula, solve my fraction problem, how to rearrange a formula with a square root in it. Online caculater with pie, 9th grade worksheets, how to solve logarithms in TI-84, simple practice examples of transposition of formulae. Think of the equation as having two separate completing-the-square problems to, well, complete. Follow these steps to give the equation a twice-over: To handle the two completions more efficiently, rewrite the equation with a space between the x terms and the y terms and with the constant on the other side: x 2 + 6x + 2y 2 – 8y = –13