How do you write the equation for a circle with points (0, 2a) (2b, 0) as ends of a diameter?

1 Answer
Jan 22, 2017

The x coordinate goes from 0 to 2b so the center is at b. Likewise, the y coordinate goes from 2a to 0 so the center is at a.
Use the equation (xh)2+(yk)2=r2;h=b,k=a and one of the points.

Explanation:

Use the equation
(xh)2+(yk)2=r2

where h=bandk=a

(xb)2+(ya)2=r2

Let's use the point (0,2a), to find the value of r:

(0b)2+(2aa)2=r2

r2=a2+b2

r=a2+b2

Here is the equation of the circle:

(xb)2+(ya)2=(a2+b2)2