Question

A circle has a radius of 4/9 units and is centered at (-6.2,5.8). Write an equation of this circle

Answer 1

`(x+6.2)^2 + (y-5.8)^2 = (16)/(81)`

Explanation:

The vertex form of the equation of a circle is
`(x-h)^2 + (y-k)^2 = r^2` where (h,k) is the center of the circle and r is the radius. This circle has center (-6.2, 5.8) and r= 4/9. Substitute h = -6.2, k = 5.8 and r = 4/9 into the vertex form. Then simplify for the equation.

`(x-h)^2 + (y-k)^2 = r^2\\(x--6.2)^2 + (y-5.8)^2 = (4)/(9)^2\\ (x+6.2)^2 + (y-5.8)^2 = (16)/(81)`