16. Consider the line 3x - 4y = 6 in the standard (x,y)

coordinate plane. For the point on this line with

x-coordinate equal to 3, what is the y-coordinate?

Find an equation of the plane containing the points P(1, 1, 11), Q(2, 6, 7),and R(-8, 4, 8).

(Let x, y, and z denote the standard coordinate variables.)

EXPLORING CONCEPTS

Using CoordinatesDescribe the surface whose equation is a coordinate equal to a constant for each of the coordinates in (a) the cylindrical coordinate system and (b) the spherical coordinate system.

Coordinates in Space What is the y-coordinate of any point in the xz-plane?