i was wondering what are some more popular ways to graph or get an idea of how a shape of an function would turn out to. the way i've learned it is to set certain variable to zero to get a certain plane. for example if i wanted the the xy plane of a function such as x^2+y^2-z^2 = 1 i would need to set the z = 0 and then solve for the y and solve for the x plugging random numbers to see how the shape is for that plane and do the same for the other two planes. which is the xz and yz. is there any other way to graph such an equation w/o using a computer and maple or something?