posted by Nikki .
Determine an equation of the circle that is tangent to both axes, has its center in the fourth quadrant and passes through the point (8, -9).
well, you know if it is tangent to both axis, the center is at r,-r
It passes through 8,-9 so the distance from that point to the center is also r.
r^2=(8-r)^2 + (-9+r)^2
r=29, or r=5
check both answers.
then put it in standard form.