# Math Insight

### Applet: Changeable paraboloid

The paraboloid $z = A x^2 + B y^2$ can be changed from a hyperbolic paraboloid to an elliptic paraboloid by changing the values of $A$ and $B$ with the sliders. When $A$ and $B$ are of the same sign, the graph is an elliptic paraboloid; when they are of different signs, the graph is a hyperbolic paraboloid.

Applet file: paraboloid_changeable.m

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