91Ó°ÊÓ

Choose from the following list the word that best completes each statement. Words may be used more than once or not at all. \(\begin{array}{ll}{\text { center }} & {\text { horizontal }} \\ {\text { circle }} & {\text { parabola }} \\ {\text { conic sections }} & {\text { radii }}\end{array} \quad \begin{array}{l}{\text { vertex }} \\ {\text { vertical }} \\ {\text { radii }}\end{array}\) A radius is the distance from a point on a circle to the ______

Graph each hyperbola. Label all vertices and sketch all asymptotes. $$ 25 x^{2}-16 y^{2}=400 $$

How can you tell from the equation of an ellipse whether its graph is horizontal or vertical?

Can an ellipse ever be the graph of a function? Why or why not?

Solve. $$\log _{x} 81=4$$

Solve. $$x^{2}+4 x=60$$

Classify each of the following as the equation of either a circle, an ellipse, a parabola, or a hyperbola. $$ 16 x^{2}+5 y^{2}-12 x^{2}+8 y^{2}-3 x+4 y=568 $$

As the foci get closer to the center of an ellipse, what shape does the graph begin to resemble? Explain why this happens.

Is it possible for a hyperbola to represent the graph of a function? Why or why not?

Factor completely. $$ 9 x^{2} y^{2}-30 x y+25 $$