How can I plot 3D TENT with MATLAB?

I have a homework with 5 question. This is the only question that I could not handle. I don't know how to do it in Matlab. (b)& (c) parts can be done in MATLAB also? Can you help me with the codes?

Question is:

   A tent that covers the area Rxy : −10 ≤ x, y ≤ 10 is described as
S : z = f(x, y) = 18 − 0.09x^2 − 0.06y^2 , (x, y) ∈ Rxy

(a) Obtain a 3D plot of the tent using MATLAB.
(b) Express the volume under the tent as an integral over Rxy and evaluate it.
(c) Express the surface area of the tent as an integral over Rxy, and find it approximately by subdividing Rxy into small squares of size 0.1 × 0.1.

Answer 1

[Matt Kindig]

For part (a), I would look up the documentation for the following two commands:

linspace  %to create your x and y domain vectors
meshgrid  %to convert x and y to a grid that you can then use to calculate z
surf      %to actually make the plot

The examples for the 'meshgrid' command should be especially useful.