Geometry
# Conic Sections

What is the area of the set of points in the bounded region ${x}^2 + {y}^2 -8x -8y +28 \leq 0 ?$

If $5{x}^2+a{y}^2+4x+5y+18=0$ is an equation that represents a circle, what is the value of $a ?$

Which of the following equations represents a different type of conic section than the others?