3times a number which is 2 less then z is nine

One expression below in undefined, and the other expression has a well defined value. which expression is undefined and explain why it has no value. which expression is defined? what is the value of that expression and how do you know? what is a different expression using a trig inverse function that is also undefined?

If w = 6 units, x = 3 units, and y = 5 units, what is the surface area of the figure? 168 units2 240 units2 144 units2 96 units2

The graph of a hyperbola is shown. what are the coordinates of a vertex of the hyperbola? (0, −4) (−3, 0) (0, 0) (0, 5)